variable

adj. changeable, fluctuating, inconstant; fickle; having a quantity that is unfixed; deviating from the norm

n. something given to variation; quantity that may represent any one of a set of values (Mathematics); star whose brightness variates at intervals (Astronomy)

In computer science and mathematics, a variable (IPA pronunciation: ) (sometimes called a pronumeral) is a symbolic representation denoting a quantity or expression. In mathematics, a variable often represents an "unknown" quantity that has the potential to change; in computer science, it represents a place where a quantity can be stored. Variables are often contrasted with constants, which are known and unchanging.
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Noun
1. something that is likely to vary; something that is subject to variation; "the weather is one variable to be considered"
(hypernym) thing
2. a quantity that can assume any of a set of values
(synonym) variable quantity
(hypernym) quantity
(hyponym) argument
3. a star that varies noticeably in brightness
(synonym) variable star
(hypernym) star
(hyponym) Polaris, North Star, pole star, polar star, polestar
4. a symbol (like x or y) that is used in mathematical or logical expressions to represent a variable quantity
(hypernym) symbol
(hyponym) placeholder
Adjective
1. liable to or capable of change; "rainfall in the tropics is notoriously variable"; "variable winds"; "variable expenses"
(antonym) invariable
(similar) changeable, uncertain, unsettled
(see-also) inconsistent
2. marked by diversity or difference; "the varying angles of roof slope"; "nature is infinitely variable"
(synonym) varying
(similar) varied
3. (used of a device) designed so that a property (as e.g. light) can be varied; "a variable capacitor"; "variable filters in front of the mercury xenon lights"
(similar) adaptable

n. variable, something variable; quantity that may represent any one of a set of values; (Statistics) variate

adj. variable, mixed, changing, inconstant

n. variable, something given to variation; quantity that may represent any one of a set of values (Mathematics); star whose brightness variates at intervals (Astronomy)