From The Collaborative International Dictionary of English v.0.48:
Valid \Val"id\, a. [F. valide, L. validus strong, from valere to
be strong. See Valiant.]
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1. Strong; powerful; efficient. [Obs.] "Perhaps more valid
arms . . . may serve to better us." --Milton.
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2. Having sufficient strength or force; founded in truth;
capable of being justified, defended, or supported; not
weak or defective; sound; good; efficacious; as, a valid
argument; a valid objection.
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An answer that is open to no valid exception. --I.
Taylor.
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3. (Law) Having legal strength or force; executed with the
proper formalities; incapable of being rightfully
overthrown or set aside; as, a valid deed; a valid
covenant; a valid instrument of any kind; a valid claim or
title; a valid marriage.
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Syn: Prevalent; available; efficacious; just; good; weighty;
sufficient; sound; well-grounded.
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