Science & Nature

Science & Nature Glossary (A to Z)


An algorithm refers to a sequence of steps taken in order to complete a given task or solve a problem.

Applied Science

Applied science refers to the practical application of scientific knowledge and principles to develop solutions, technologies, or innovations that address real-world problems, enhancing various fields such as medicine, engineering, and industry.

Applied Force

Applied force is the force that is applied by one object to another to cause the object to change its state of rest, its direction of motion, or its size or shape.

Angular Velocity

Angular velocity is the rate at which an object rotates around a fixed point. It is measured in units of radians per second and can be thought of as how quickly an object spins.

Associative Learning

Associative learning is a kind of learning that subjects undergo in their environment. It’s where subjects make associations or links between two things that were not associated with each other before. 

Bernoulli’s Principle

Bernoulli’s Principle states that as the speed of a fluid increases, its pressure decreases. It describes the inverse relationship between fluid velocity and pressure in a steady flow, foundational in understanding airflow dynamics and lift in aerodynamics.


Chemotaxis is a phenomenon where somatic cells, single-celled and multicellular organisms, and bacteria direct their movement according to specific chemicals in the environment.


Centrifugation is a process that uses centrifugal force to separate substances of varying densities within a mixture. By spinning at high speeds, denser components move outward, forming layers, allowing the isolation or purification of materials such as cells or molecules.

Classical Conditioning

Classical conditioning is a type of learning where an organism associates two stimuli, leading to a learned response. It involves pairing a neutral stimulus with an unconditioned stimulus to evoke a conditioned response.

Colloid Mixture

A colloid mixture consists of small particles dispersed in another substance, creating a homogeneous yet not fully dissolved solution. It exhibits intermediate particle size between solutions and suspensions.

Combinational Logic Circuits

Combinational logic circuits are digital circuits without memory elements, producing outputs based solely on present input values. They perform specific logic functions, such as addition, subtraction, or comparison, without storing data.

Combination Reaction

A combination reaction is a special category of reactions where two or more substances react together to form one compound.

Combined Gas Law

The combined gas law describes the relationship between the pressure, volume, and temperature of a fixed amount of gas. It is a combination of three gas laws: Boyle’s law, Charles’ law, and Gay-Lussac’s law.

Compound Machines

Compound machines are complex systems made of multiple simple machines working together to perform tasks. They leverage the combined mechanical advantages of various components to accomplish specific functions or actions.

Compressional Waves

Compressional waves, also known as longitudinal waves, transmit energy by causing particles to oscillate parallel to the direction of wave propagation, typically seen in sound waves and seismic vibrations.

Concentration Gradient

Concentration gradient is a term commonly used in biology and physical chemistry to describe the difference in concentration of a solute between two regions. This difference can occur in cells, tissues, organs, or even solutions outside the body.

Concurrent Forces

Concurrent forces are multiple forces acting on a single point or object, where their lines of action intersect at a common point, resulting in a combined effect on the object.

Contact Forces

Contact forces are interactions between objects in direct physical contact, generating forces through direct touch or contact.

Convergent Boundary

A convergent boundary marks the area where two tectonic plates collide or meet each other.


Deposition refers to the process of laying sediments when the transporting agent ceases to transport or slows down.

Decomposition Reaction

A decomposition reaction is a chemical process where a compound breaks down into simpler substances, often due to heat, electricity, or exposure to other substances, resulting in multiple products.

Disruptive Selection

Disruptive selection is a kind of natural selection in biology where individuals with extreme traits are favored to survive.

Double Replacement Reaction 

A double replacement reaction is a chemical process where two compounds exchange ions, leading to the formation of two new compounds, typically occurring in aqueous solutions and producing a precipitate or gas.

Edge Effect

An edge effect is the end result of an abrupt transition between two distinct natural habitats that are located within the same ecosystem and are adjacent to one another.


Effusion occurs when gaseous molecules move across a concentration gradient, albeit through a tiny opening or a semi-permeable surface with a diameter smaller than the molecule’s mean free path.

Enumerative Induction

Enumerative induction is an inductive inference involving generalizations based on a finite number of specific observations. It is a standard method used in scientific research and can help test hypotheses and make predictions.

Hypothesis Testing 

Hypothesis testing in statistics is a method used to assess the validity of a claim or hypothesis about a population parameter, utilizing sample data to make inferences and draw conclusions.

Facilitated Diffusion

Facilitated diffusion is a passive transport process where specific molecules move across a cell membrane with the assistance of transport proteins, following a concentration gradient without energy expenditure.

First Class Levers

A first-class lever is a mechanical system where the fulcrum lies between the effort and the load.

Foliated Rocks

Foliated rocks are metamorphic rocks characterized by a layered or banded structure due to the alignment of mineral grains under heat and pressure.

Harmful Chemical Reactions 

These are toxic or hazardous chemical reactions can take place at home, at the workplace, or in industrial settings.

Hess’s Law

Hess’s law, also referred to as the law of heat summation, looks at what happens to enthalpy or heat changes during chemical reactions.

Ideal Gas Law

The ideal gas law is a mathematical formula that relates pressure, volume, temperature, and the number of particles of a gas. It demonstrates the relationship between gas properties, allowing scientists to predict gas behavior.

Inclined Plane

An inclined plane is a simple machine that reduces the force needed to lift an object by allowing it to move up or down along a sloped surface, altering the effort required.

Incompressible Fluid

Incompressible fluids are fluids that experience extremely minute, negligible density changes in the face of pressure or external force.

 Input and Output Devices

An input device controls signals to an information processing system of an electronic device and sends data to the system. A piece of instrument that receives information from an electronic device is called an output device.

Instantaneous Rate of Change

The instantaneous rate of change refers to the rate of change at a specific moment, determined by finding the slope of the tangent line to a curve at a single point.

Intrusive Igneous Rocks

Also known as plutonic rocks, intrusive igneous rocks solidify deep inside the earth’s interior.

Kinetic Energy

Kinetic energy is the energy possessed by an object due to its motion. It is dependent on the object’s mass and velocity, describing the energy of motion in dynamic systems.

Law of Conservation of Mass

The Law of Conservation of Mass states that in a closed system, the total mass remains constant over time; mass cannot be created or destroyed, only rearranged or transformed in reactions.

Law Of Segregation

The law of segregation is a principle in genetics that states that during the formation of gametes (sperm and egg cells), the two alleles (different versions of a gene) for a trait separate from each other so that each gamete carries only one allele.

Lenz’s Law

Lenz’s Law is a fundamental law of electromagnetism that describes the direction of an induced electric current in a conductor when the magnetic field around it changes.

Metamorphic Rocks

Metamorphic rocks are formed within the earth’s crust when the existing rocks are subjected to high temperature and pressure.

Motion Energy

Motion energy, also known as kinetic energy, is the energy possessed by an object due to its motion. It arises from an object’s velocity and mass, demonstrating the capacity to perform work or cause changes while in motion.

Net Force

Net force is the overall force acting on an object, determined by combining all individual forces acting upon it. It influences the object’s motion, direction, and acceleration, reflecting the sum of all applied forces.

Null and Alternative Hypothesis

In statistics, the null hypothesis suggests no significant difference or effect, while the alternative hypothesis proposes the existence of a significant difference, effect, or relationship between variables. Statistical testing aims to accept or reject the null hypothesis based on evidence.


Ores are naturally occurring deposits of geological materials (or rocks) that occur in sufficient quantity and contain enough elements to permit their recovery and extraction for economic gain.


Outliers in data analysis are data points that significantly differ from the rest of the dataset, potentially indicating errors, rare occurrences, or genuine deviations that require special consideration or investigation.

Passive Transport

Passive transport is a biological process where substances move across a cell membrane without requiring energy. It occurs along the concentration gradient, from an area of high to low concentration.


Also known as axioms or premises, postulates are statements or positions that are taken to be true. 

Precipitation Reaction

Precipitation reaction occurs when multiple ionic bonds combine and produce an insoluble salt. For a precipitation reaction to take place, the reactants should be in their ionic states and in a medium, most notably an aqueous solution.

Prezygotic Barriers

A prezygotic barrier or isolation is a situation in reproduction where the eggs of an organism fail to be fertilized.


Producers in biology are organisms, mainly plants, that manufacture their own food through photosynthesis or chemosynthesis, serving as the primary source of energy for ecosystems.

Quantitative Observation

Quantitative observation involves gathering data or information using numerical values and measures. It employs precise measurements or counts to describe, analyze, or quantify aspects of a phenomenon or subject under study.


A queue is an abstract data structure with a linear form that shows the order in which operations should be done.


Rarefaction refers to the region in a longitudinal wave where particles are spread apart, creating a decrease in density. It occurs between compressions and is a phase of wave propagation.

Rectilinear Motion

Rectilinear motion is the motion of an object at a constant direction of velocity along a straight line.

Reverse Osmosis

Reverse osmosis is a water purification process where pressure is applied to force water through a semipermeable membrane, removing impurities and contaminants. This technology separates solvents from a solution, producing clean drinking water by filtering out molecules, ions, and larger particles.

Second-Class Levers

Second-class levers are mechanical systems where the load is situated between the fulcrum and the effort.

Sedimentation (Nature)

Sedimentation occurs when particles (also called sediments) come to rest at the bottom of lakes or other water bodies after being transported over some distance.

Simple Machines

Simple machines are basic mechanical devices that alter the force or direction of an applied effort.

Single Displacement Reaction

This is a reaction where an element replaces another element in a compound during a reaction. The starting materials in the reaction are an element and a compound that react together to produce another element and another compound.

 Suspension Mixture

A suspension mixture is a heterogeneous combination where particles of a substance are dispersed but not dissolved in another medium, remaining suspended due to gravity and requiring agitation for stability.

Stabilizing Selection

Stabilizing selection is an evolutionary process where the intermediate traits within a population are favored, leading to the reduction of extreme variations. It maintains the status quo by favoring traits near the average and decreasing genetic diversity within a population.

Third Class Levers

 Third class levers are those levers in which the effort is located between the fulcrum and the effort.

Transform Boundary

A transform boundary (also called a transform fault), is a fractured area or Faultline on the earth’s surface where two tectonic plates slide horizontally past each other.


Tonicity refers to the concentration of solutes on either side of a semipermeable membrane that separates two solutions. 


Torque is the measure of a force’s ability to cause rotational motion around an axis. It’s calculated as the product of the force and the distance from the axis of rotation.

Vestigial Structures

Vestigial structures are anatomical features or organs in organisms that have diminished in size or lost their original function through evolution, often serving no apparent purpose in the present species.

Weak Nuclear Forces

Weak nuclear forces are fundamental forces in particle physics responsible for certain types of radioactive decay and interactions between particles. They facilitate processes like beta decay and neutrino absorption, mediating interactions within atomic nuclei involving neutrinos and leptons.

Wheel and Axle

A wheel and axle is a simple machine composed of a wheel attached to a smaller axle, enabling the transfer of force to accomplish tasks like lifting or moving objects more efficiently.