The Branched Timeline Scientific Dictionary

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This page is a dictionary for Scientific Terms where the meanings that will be given are verified and up to date. Words written will not be in any particular order so people who want to find a particular word meaning may do Ctrl-F and find whereas people who wish to build up their scientific vocabulary can just read it. If you don't find a word whose meaning you want to know then please leave the word in the comment section. Few words will be added everyday. 

The sources of Scientific Dictionary will be from various leading scientists, scientific organisations and articles.

Word-Meaning 

1. WIMP (Weakly Interacting Massive Particles) - WIMPs are the subatomic particles which are not made up of ordinary matter. They are "weakly interacting" because they can pass through ordinary matter without any effects. They are "massive" in the sense of having mass (whether they are light or heavy depends on the particle). The prime candidates include neutrinos, axions, and neutralinos.
2. MACHO ( Massive Astronomical Compact Halo Objects) - MACHOs are objects ranging in size from small stars to super massive black holes. MACHOS are made of ordinary matter (like protons, neutrons and electrons). They may be black holes, neutron stars, or brown dwarfs.  Astronomers have been detecting MACHOs using their gravitational effects on the light from distant objects. In formulating his theory of gravity, Einstein discovered that the gravitational attraction of a massive object can bend the path of a light ray, much like a lens does. So when a massive object passes in front of a distant object (e.g. a star or another galaxy), the light from the distant object is "focused" and the object appears brighter for a short time. Astronomers search for MACHOs (usually brown dwarfs) in the halo of our galaxy by monitoring the brightness of stars near the center of our galaxy and of stars in the Large Magellanic Cloud.
3. Spheroid - It is a geometrical figure that best fits the earth. It is smooth. Spheroid has a mathematical equation with definite parameters. In the case of the earth, the spheroid is actually an oblate spheroid which is obtained by rotating an ellipse about its minor axis. The surface of the spheroid very nearly coincides with the mean sea level. Its semi-major axis is 6378137 m long and semi-minor axis is 6356752 m long.
4. Geoid - The geoid is the actual shape of the Earth. It is undulating. Geoid cannot be described by a mathematical equation. This model is used to measure surface elevations with a high degree of accuracy. It is a model of global mean sea level.    
5. Singularity: It is present at the very centre of a black hole where matter has collapsed into a region of infinite density called singularity. All the matter and energy that fall into black hole ends up here. The laws of quantum mechanics are not valid after this point.
6. Event Horizon: This is the radius around a singularity where matter and energy cannot escape the black hole's gravity. This is the 'point of no return'. This is the "black" part of the "black hole".
7. Relativistic Jets: When a black hole feeds on star, gas or dust, the meal produces jets of particles and radiation, blasting out from black hole at near the speed of light. They can go to thousands of light years into space. 
8. Accretion Disc: The disc of superheated gas and and dust whirls around a black hole at immense speeds, producing electromagnetic radiations (X-rays, visible, infrared and radio) and reveal the black hole's location. Some of the material is doomed to cross the event horizon while the others may be forced out to create relativistic jets. The inner edge of an accretion disc is the last place that material can orbit safely without the risk of falling past the point of no return, this inner edge is called 'Innermost Stable Orbit'
9. Photon Sphere: Although the black hole itself is dark, photons are emitted from nearby hot plasma in jets or an accretion disc. In the absence of gravity, these photons would travel in straight lines, but just outside the event horizon, gravity is strong enough to bend their paths so that we see a bright ring surrounding a roughly circular dark "shadow".
10. White hole: It is a hypothetical region of spacetime singularity which is just opposite of a black hole. Nothing can enter a white hole though the objects inside a white hole can leave and interact with the outside world. Its event horizon is a "point of no admission".  
11. Supernova: It is the biggest explosion that humans have ever seen. Each blast is the extremely bright, super-powerful explosion of a star. 
12. Multiverse: A hypothetical space or realm consisting of a number of universes, of which our own universe is only one.
13. Light Year: A unit of astronomical distance equivalent to the distance that light travels in one year, which is 9.4607 × 1012 km (nearly 6 million million miles).
14. Plasma: It is superheated matter – so hot that the electrons are ripped away from the atoms forming an ionized gas.
15. Solar Mass: A solar mass is the mass of the sun. Or, more precisely, it's 1.989 x 10^30 kilograms, about 333,000 Earths.
16. Dark Matter: It is a hypothetical, invisible and unknown mass that make up the most of the universe. Universe is made up of nearly 80-85% dark matter.
17. Neutron Star: A neutron star is the collapsed core of a massive supergiant star, which had a total mass of between 10 and 25 solar masses, possibly more if the star was especially metal-rich.
18. White Dwarf: A white dwarf, also called a degenerate dwarf, is a stellar core remnant composed mostly of electron-degenerate matter. A white dwarf is very dense: Its mass is comparable to that of the Sun, while its volume is comparable to that of Earth. A white dwarf's faint luminosity comes from the emission of stored thermal energy; no fusion takes place in a white dwarf. 
19. Hawking Radiation: Thermal radiation that is theorized to be released outside a black hole's event horizon because of relativistic quantum effects.
20. Paradox - A seemingly absurd or contradictory statement or proposition which when investigated may prove to be well founded or true. Eg, the uncertainty principle leads to all sorts of paradoxes, like the particles being in two places at once.
21. Daughter Universe Theory- The theory of quantum mechanics, which reigns over the tiny world of subatomic particles, suggests another way multiple universes might arise. Quantum mechanics describes the world in terms of probabilities, rather than definite outcomes. And the mathematics of this theory might suggest that all possible outcomes of a situation do occur — in their own separate universes. For example, if you reach a crossroads where you can go right or left, the parent universe gives rise to two daughter universes: one in which you go right, and one in which you go left.
22. Butterfly Effect - It is a concept invented by the American meteorologist Edward N. Lorenz to highlight the possibility that small causes may have momentous effects. In chaos theory, the butterfly effect is the sensitive dependence on initial conditions in which a small change in one state of a deterministic nonlinear system can result in large differences in a later state. Eg, Flutter of a butterfly in one region on earth may cause a tornado in the other region. 
23. Time Dilation - It can be explained by special/general relativity but explaining in the most simple words it means if you manage to come to a place with very high gravity (generally a black hole) or if you can manipulate gravity's power then the gravity will bend time so much that 1 minute for you can be 10 years or 100 years on Earth.
24. Wormholes - They can be understood through Einstein Field Equations but again putting in very easy words, they can be thought as a tunnel or a bridge that link 2 points of spacetime.
25. Spacetime - Its a four dimensional model made when 3 dimensions of space and 1 dimension of time fuse together. 
26. Black Hole - A black hole is a region of spacetime where gravity is so strong that nothing—no particles or even electromagnetic radiation can escape from it. The theory of general relativity predicts that a sufficiently compact mass can deform spacetime to form a black hole.
27. Matter - Anything that has mass and occupies space.
28. Quark - It is a fundamental constituent of matter and is defined as an elementary particle. These quarks combine to produce composite particles called hadrons, the most stable of which are neutrons and protons. There are 6 types of quark - up, down, charm, strange, top and bottom.
29. Leptons - It is a member of a class of subatomic particles that respond only to the electromagnetic force, weak force, and gravitational force and are not affected by the strong force. Leptons are said to be elementary particles. Leptons can either carry one unit of electric charge or be neutral. The charged leptons are the electrons, muons, and taus. Each of these types has a negative charge and a distinct mass. There are 6 types of leptons - Electron, Neutrino, Muon, Muon Neutrino, Tau, Tau Neutrino.
30. Bosons - Bosons are sometimes called force particles, because it is the bosons that control the interaction of physical forces, such as electromagnetism and possibly even gravity itself. In particle physics, a boson is a type of particle that obeys the rules of Bose-Einstein statistics. These bosons also have a quantum spin with contains an integer value.
31. Gravitons - A hypothetical particle with zero charge and rest mass that is held to be the quantum of the gravitational field.
32. Hadrons - Hadron is defined as the subatomic particle made of quarks, gluons and anti-quarks. Hadrons are the heaviest particles. It is composed of two or more quarks that are held strongly by the electromagnetic force. Every individual quark has functional electric charges, these combine such that hadrons carry a net integer electric charge. There are 2 types of hadrons - Mesons and Baryons.
33. Meson - Meson, any member of a family of subatomic particles composed of a quark and an antiquark. Mesons are sensitive to the strong force, the fundamental interaction that binds the components of the nucleus by governing the behaviour of their constituent quarks.
34. Baryons - Baryons are heavy subatomic particles that are made up of three quarks. Both protons and neutrons, as well as other particles, are baryons.
35. Brown Dwarfs - Brown dwarfs are objects which have a size between that of a giant planet like Jupiter and that of a small star. In fact, most astronomers would classify any object with between 15 times the mass of Jupiter and 75 times the mass of Jupiter to be a brown dwarf. Given that range of masses, the object would not have been able to sustain the fusion of hydrogen like a regular star; thus, many scientists have dubbed brown dwarfs as "failed stars".
36. Higgs Boson - It is an elementary particle in the Standard Model of particle physics produced by the quantum excitation of the Higgs field, one of the fields in particle physics theory. In the Standard Model, the Higgs particle is a massive scalar boson with zero spin, no electric charge, and no colour charge. It is also very unstable, decaying into other particles almost immediately.
37. Mass - Amount of matter present in a body force of resistance that we get when we travel through the Higgs Boson field.
38. Subatomic Particle - Particles smaller than an atom. Examples of such is in the Standard Model of Elementary Particles.
39. Axions - A hypothetical particle that may be a constituent of dark matter. Super-lightweight particle about one-millionth the mass of the electron. The existence of the axion is hinted at by subtleties that the Standard Model predicts in the behaviour of quarks. Efforts to detect it exploit the fact that in a very strong magnetic field, an axion can transform into a photon.
40. Neutralinos - They are hypothetical particles that may explain what dark matter is made up of. The lightest of a putative new class of particles that are heavier counterparts of the known particles.
41. Weight - Force experienced because of gravity.
42. Star - A star is any massive self-luminous celestial body of gas that shines by radiation derived from its internal energy sources.
43. Halo - Region of space outside the disc (shape of a galaxy).
44. Gravitation - Movement, or a tendency to move, towards a centre of gravity, as in the falling of bodies to the earth.
• Gravity - Force responsible for gravitation.
45. Light - A electromagnetic radiation that has a speed of 299792458 m/s
46. Large Magellanic Cloud - Nearly 200,000 light-years from Earth, the Large Magellanic Cloud, a satellite galaxy of the Milky Way, floats in space, in a long and slow dance around our galaxy. Vast clouds of gas within it slowly collapse to form new stars. In turn, these light up the gas clouds in a riot of colors. LMC is ablaze with star forming regions.
47. Astronomical - Relating to astronomy.
• Astronomy - Astronomy is the study of everything in the universe beyond Earth's atmosphere. That includes objects we can see with our naked eyes, like the Sun, the Moon, the planets, and the stars. It also includes objects we can only see with telescopes or other instruments, like faraway galaxies and tiny particles.
48. Aberration - 
• Biology - A characteristic that deviates from the normal type.
• Optics - The failure of rays to converge at one focus because of limitations or defects in a lens or mirror.
• Astronomy - The apparent displacement of a celestial object from its true position, caused by the relative motion of the observer and the object.
49. Chromatic Aberration- The material effect produced by the refraction of different wavelengths of electromagnetic radiation through slightly different angles, resulting in a failure to focus. It causes colored fringes in the images produced by uncorrected lenses.
50. Spherical Aberration - Rays reflect or refract from points at different distances from the principal axis. In general they meet each other at different points. Thus the image of the point object is a  blurred surface. Such a defect is called spherical aberration.
51. Monochromatic Aberration - It includes spherical aberration, Coma, Astigmatism, Curvature and Distortion.
52. Lens - A lens is a transmissive optical device which focuses or disperses a light beam by means of refraction. A simple lens consists of a single piece of transparent material, while a compound lens consists of several simple lenses (elements), usually arranged along a common axis. Lenses are made from materials such as glass or plastic, and are ground and polished or molded to a desired shape.
53. Galaxy - A galaxy is a huge collection of gas, dust, and billions of stars and their solar systems, all held together by gravity.
54. Mean Sea Level - The mean sea level is a scientific term that is used to describe the average height of the oceans around the world.
55. Density - Mass per unit volume. Ratio of mass and volume.
56. Energy - Capacity to do work. It may exist in potential, kinetic, thermal, electrical, chemical, nuclear, or other various forms. 
57. Force - Any push or pull that tends to maintain or alter the motion of a body or to distort it.
58. Quantum Mechanics - Quantum mechanics is the branch of physics relating to the very small. It results in what may appear to be some very strange conclusions about the physical world. At the scale of atoms and electrons, many of the equations of classical mechanics, which describe how things move at everyday sizes and speeds, cease to be useful. In classical mechanics, objects exist in a specific place at a specific time. However, in quantum mechanics, objects instead exist in a haze of probability; they have a certain chance of being at point A, another chance of being at point B and so on. 
59. Quantum - 
• It is the minimum amount of any physical entity involved in an interaction. 
• Discrete natural unit, or packet, of energy, charge, angular momentum, or other physical property.  
60. Angular Momentum - In physics, angular momentum (rarely, moment of momentum or rotational momentum) is the rotational equivalent of linear momentum. It is an important quantity in physics because it is a conserved quantity—the total angular momentum of a closed system remains constant.
61. Charge - Electric charge is the basic physical property of matter that causes it to experience a force when kept in an electric or magnetic field. An electric charge is associated with an electric field and the moving electric charge generates a magnetic field.
62. Classical Mechanics - A physical theory describing the motion of macroscopic objects, from projectiles to parts of machinery, and astronomical objects, such as spacecraft, planets, stars, and galaxies. For objects governed by classical mechanics, if the present state is known, it is possible to predict how it will move in the future (determinism), and how it has moved in the past (reversibility).
63. Time - 
• According to relativity - In relativity, time is certainly an integral part of the very fabric of the universe and cannot exist apart from the universe, but, if the speed of light is invariable and absolute, Einstein realized, both space and time must be flexible and relative to accommodate this. 
• According to classical mechanics - Time in physics is defined by its measurement: time is what a clock reads. In classical, non-relativistic physics, it is a scalar quantity and, like length, mass, and charge, is usually described as a fundamental quantity. Time can be combined mathematically with other physical quantities to derive other concepts such as motion, kinetic energy and time-dependent fields. According to Newton time is naturally an absolute quantity and does not depend on any other outside object and proceeds uniformly. So time is universal and it moves at a fixed rate which does not depend on object or observer. 
64. Motion - The action or process of moving or being moved. 
65. Volume - Volume is the quantity of three-dimensional space enclosed by a closed surface. 
66. Solar System - The solar system is the sun and everything that orbits around it. It includes the planets and their moons as well as numerous asteroids and comets. These objects are all held in orbit around the sun by the sun's strong gravity. 
67. Solid - The type of matter which is rigid in structure and opposes the change in its shape and volume. The particles of a solid are tightly bound and well-arranged in a regular pattern, which does not allow the particles to move freely from one place to another. The particles continuously vibrate and twist, but there is no motion, as they are too close to each other. As the intermolecular attraction is maximum in solids, and because their shape is fixed, and the particles stay, where they are set. In addition to this, the compression of solid is very tough, as the spaces between molecules are already very less.
68. Liquid - A free flowing substance of constant volume having consistency is called as the liquid. It is a type of matter which do not have its shape but takes the shape of the vessel, in which it is held. It contains small particles, which are held tightly by intermolecular bonds. One of the unique property of liquid is surface tension, a phenomenon which makes the fluid possess the minimum surface area. The compression of liquid is a nearly difficult, due to less gap between particles. The particles are closely bound, but not as tightly as in the case of solid. Thus allowing the particles to move around and mix with one another.
69. Gas - The state of matter which diffuses freely in all directions and fills the entire space available, regardless of the quantity. It is made up of particle that does not have a certain shape and volume. The particles can be individual atoms or elemental molecules or compound molecules. In gases, the molecules are loosely held, and so there is a lot of space between molecules to move freely and constantly. Due to this characteristic, the gas has the ability to fill any container, as well as it can be easily compressed.
70. Dispersion - Dispersion, sometimes more specifically called ​chromatic dispersion​, occurs when the velocities of different components of a light wave depend on the wavelengths of those components. Specific types of chromatic dispersion are defined by what causes the dependence of velocity on wavelength.

71. Abiotic stress - The non-living environmental factors like drought, extreme cold, heat, high winds that has negative effect on the organisms in a specific environment is known as the abiotic stress.

72. Absolute Zero - 

    The lowest theoretical temperature where all the molecular activities cease to continue. The absolute temperature is 0K= -273.16°C

73. Abzyme - 

    An antibody that has an ability to catalyze a chemical reaction by binding and stabilizing the state of transition of an intermediate compound that is selected to carry out an biological reaction is known as an abzyme.

74. Accretion - 

    Accumulation of dust and gas into larger bodies.

75. Achondrite - 

    The stony meteorites without chondrules that have been crystallized from magma are known as achondrite.

76. Acid - 

    A sour tasting, corrosive substance - the opposite of a base substance. Acidic solutions will turn a litmus red.

77. Acid Rain - 

    Rainfall with a greater acidity than normal.

78. Adsorption - 

    Process that occurs when a gas or liquid solute accumulates on the surface of a solid or, more rarely, a liquid (adsorbent), forming a molecular or atomic film (the adsorbate). It is different from absorption, in which a substance diffuses into a liquid or solid to form a solution.

79. Adult Stem Cell - 

    A specialized cell that is needed for growth, wound healing and tissue regeneration. Adult stem cells are found in all tissues and organs of animals and plants.

80. Aerosols - 

    Liquid or solid particles that are suspended in air or a gas. Also referred to as particulate matter.

81. Z-DNA

    - 

    The region of DNA that has a left handed helix with alternating purines and pyrimidines that may be a site for a DNA-binding protein is known as Z-DNA. Know more on Structure of Mitochondrial DNA

82. Zebra Fish - 

     

    The Zebra fish is one of many model organisms used in biomedical research to understand development of higher organisms, the functioning of nervous systems, and fundamental aspects of physiology and the cause of diseases.

83. Zodiac - Twelve constellations dividing the ecliptic into approximately equal parts. Each month the Sun is in a different constellation of the zodiac.

84. Zoology - The branch of science under biology that studies the structure, function, behavior and evolution of animals is known as zoology.

85. Zooplankton - Microscopic animals that live in the water column of oceans, seas, and bodies of fresh water. The smallest zooplankton can be characterized as recyclers of water-column nutrients and often are closely tied to measures of nutrient enrichment. Larger zooplankton are important food for forage fish species and larval stages of all fish.

86. Zooxanthellae - Unicellular yellow-brown (dinoflagellate) algae which live symbiotically in the gastrodermis of reef-building coral.

87. Zygote - A zygote is a fertilized egg containing two sets of chromosomes, one from the egg (oocyte) and one form the sperm. The zygote is a single cell and the result of a fusion between two gametes, an egg (female) and one sperm cell (male)

88. Y-Chromosome - One of two sex chromosomes in higher organisms that defines the gender of the adult. In almost all sexually reproducing organisms, the Y-chromosome defines male characteristics.

89. Yellow Fever - T

    he transmission of acute viral disease by the bite of Aedes aegypti mosquito is known as yellow fever.

90. Yolk - The part of an egg that helpsin feeding the embryo as it develops in an egg.