Producing the desired results; efficacious: valid methods.
Having legal force; effective or binding: a valid title.
Logic
Containing premises from which the conclusion may logically be derived: a valid argument.
Correctly inferred or deduced from a premise: a valid conclusion.
Archaic Of sound health; robust.
[French valide, from Old French, from Latin validus, strong, from valēre, to be strong; see wal- in Indo-European roots.]
va·lid'i·ty, val'id·ness n., val'id·ly adv.
Synonyms: These adjectives describe assertions, arguments, conclusions, reasons, or intellectual processes that are persuasive because they are well founded. What is valid is based on or borne out by truth or fact or has legal force: a valid excuse; a valid claim.
What is sound is free from logical flaws or is based on valid reasoning: a sound theory; sound principles.
Something cogent is both sound and compelling: cogent testimony; a cogent explanation. Convincing implies the power to dispel doubt or overcome resistance or opposition: convincing proof.
1571, "having force in law, legally binding," from M.Fr. valide, from L. validus "strong, effective," from valere "be strong" (see valiant). The meaning "supported by facts or authority" is first recorded 1648. Validate (v.) is recorded from 1648.
Main Entry: val·id Pronunciation: 'va-l&d Function: adjective 1: having legal efficacy or force <a valid license>;
especially: executed with proper authority and form <a valid contract> <a valid search> 2: having a legitimate basis :JUSTIFIABLE <a valid reason for terminating the employee> 3: appropriate to the end in view
—va·lid·i·ty/v&-'li-d&-tE/noun —val·id·lyadverb
Valid A dataflow language. ["A List-Processing-Oriented Data Flow Machine Architecture", Makoto Amamiya et al, AFIPS NCC, June 1982, pp. 143-151]. (1995-02-14)
Val"iant\, a. [OE. valiant, F. vaillant, OF. vaillant, valant, originally p. pr. of OF. & F. valoir to be worth, L. valere to be strong. See Wield, and cf. Avail, Convalesce, Equivalent, Prevail, Valid.]1. Vigorous in body; strong; powerful; as, a valiant fencer. [Obs.] --Walton. 2. Intrepid in danger; courageous; brave. A valiant and most expert gentleman. --Shak. And Saul said to David . . . be thou valiant for me, and fight the Lord's battles. --1 Sam. xviii. 17. 3. Performed with valor or bravery; heroic. "Thou bearest the highest name for valiant acts." --Milton. [The saints] have made such valiant confessions. --J. H. Newman. -- Val"iant*ly, adv. -- Val"iant*ness, n.
Val"id\, a. [F. valide, F. validus strong, from valere to be strong. See Valiant.]1. Strong; powerful; efficient. [Obs.] "Perhaps more valid arms . . . may serve to better us." --Milton. 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. An answer that is open to no valid exception. --I. Taylor. 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. Syn: Prevalent; available; efficacious; just; good; weighty; sufficient; sound; well-grounded.
Val"i*date\, v. t. [See Valid.] To confirm; to render valid; to give legal force to. The chamber of deputies . . . refusing to validate at once the election of an official candidate. --London Spectator.
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