Reaction rate constant, often denoted k or λ, a value characterizing the speed of a chemical reaction

The constant term of a polynomial, which is the term of degree 0

Physical constant, a physical quantity that is generally believed to be both universal in nature and constant in time, such as c, the speed of light, or h, the Planck constant

Cosmological constant, usually denoted by Λ, a parameter modifying the original equations of the theory of general relativity, introduced by Einstein and important for determining the ultimate fate of the universe as predicted by the theory

Time constant, usually denoted by τ, a value characterizing the frequency response of a first-order, linear time-invariant system

Arbitrary constant of integration, usually denoted by C, expressing a free parameter arising in integration

Constans, a Roman Emperor who ruled from 337 to 350

Mathematical constant, a number that arises naturally in mathematics, such as π and e

A constant function, a function that maps all arguments to one same value

A coefficient or other parameter in a formula, given as a number or as a variable, but not being considered one of the arguments

Constant (given name), a human given name

Logical constant, a symbol in symbolic logic that has the same meaning in all models, such as the symbol "=" for "equals".

Constant time, or O(1) time, in computational complexity theory, meaning a computation time needed for solving a problem that does not depend on the size of the input data

Constant (surname), a human surname

USS Constant