/vair"ee euh beuhl/, adj.1. apt or liable to vary or change; changeable: variable weather; variable moods.2. capable of being varied or changed; alterable: a variable time limit for completion of a book.3. inconstant; fickle: a variable lover.4. having much variation or diversity.5. Biol. deviating from the usual type, as a species or a specific character.6. Astron. (of a star) changing in brightness.7. Meteorol. (of wind) tending to change in direction.8. Math. having the nature or characteristics of a variable.n.9. something that may or does vary; a variable feature or factor.10. Math., Computers.a. a quantity or function that may assume any given value or set of values.b. a symbol that represents this.11. Logic. (in the functional calculus) a symbol for an unspecified member of a class of things or statements. Cf. bound variable, free variable.12. Astron. See variable star.13. Meteorol.a. a shifting wind, esp. as distinguished from a trade wind.b. variables, doldrums (def. 2a).[1350-1400; late ME < L variabilis, equiv. to vari(us) VARIOUS + -abilis -ABLE]Syn. 3. vacillating, wavering, fluctuating, unsteady, mercurial.Ant. 1, 3. constant.
* * *ICommonly used variables include x and y (real-number unknowns), z (complex-number unknowns), t (time), r (radius), and s (arc length). Variables should be distinguished from coefficients, fixed values that multiply powers of variables in polynomials and algebraic equations. In the quadratic equation ax2 + bx + c = 0, x is the variable and a, b and c are coefficients whose values must be specified to solve the equation. In translating word problems into algebraic equations, quantities to be determined can be represented by variables.II(as used in expressions)
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