Constant (k&obreve_;nst&aitalic_;nt), a. [L. onstans, -antis, p. pr. of constare to stand firm, to be consistent; con- + stare to stand: cf. F. constant. See Stand and cf. Cost, v. t.] 1. Firm; solid; fixed; immovable; -- opposed to fluid. [Obs.]
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If . . . you mix them, you may turn these two fluid liquors into a constant body. Boyle.
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2. Not liable, or given, to change; permanent; regular; continuous; continually recurring; steadfast; faithful; not fickle. Opposite of changeable and variable.
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Both loving one fair maid, they yet remained constant friends. Sir P. Sidney.
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I am constant to my purposes. Shak.
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His gifts, his constant courtship, nothing gained. Dryden.
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Onward the constant current sweeps. Longfellow.
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3. (Math. & Physics) Remaining unchanged or invariable, as a quantity, force, law, etc.
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4. Consistent; logical. [Obs.] Shak.

Syn. -- Fixed; steadfast; unchanging; permanent; unalterable; immutable; invariable; perpetual; continual; resolute; firm; unshaken; determined. -- Constant, Continual, Perpetual. These words are sometimes used in an absolute and sometimes in a qualified sense. Constant denotes, in its absolute sense, unchangeably fixed; as, a constant mind or purpose. In its qualified sense, it marks something as a “standing” fact or occurence; as, liable to constant interruptions; constantly called for. Continual, in its absolute sense, coincides with continuous. See Continuous. In its qualified sense, it describes a thing as occuring in steady and rapid succession; as, a round of continual calls; continually changing. Perpetual denotes, in its absolute sense, what literally never ceases or comes to an end; as, perpetual motion. In its qualified sense, it is used hyperbolically, and denotes that which rarely ceases; as, perpetual disturbance; perpetual noise; perpetual intermeddling.
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