- (when tr, may take a clause as object)
to state (something) formally as a declaration of fact to declare or give (evidence) under oath, esp in court - when intr, often followed by to:
to be evidence (of); serve as witness (to) - (transitive)
to declare or acknowledge openly
WordReference Random House Learner's Dictionary of American English © 2025
tes•ti•fy /ˈtɛstəˌfaɪ/USA pronunciation
v., -fied, -fy•ing.
WordReference Random House Unabridged Dictionary of American English © 2025- Lawto state or declare under oath, usually in court: [no object]The witness was afraid to testify.[~ + (that) clause]testified that she had seen him fleeing from the scene of the crime.
- to give or provide evidence about something:[~ + to + object]This excellent book testifies to the author's ability.
tes•ti•fy
(tes′tə fī′),USA pronunciation v., -fied, -fy•ing.
v.i.
v.t.
tes′ti•fi′er, n.
v.i.
- to bear witness;
give or afford evidence. - Lawto give testimony under oath or solemn affirmation, usually in court.
- to make solemn declaration.
v.t.
- to bear witness to;
affirm as fact or truth;
attest. - to give or afford evidence of in any manner.
- Lawto state or declare under oath or affirmation, usually in court.
- to declare, profess, or acknowledge openly.
- Latin testificārī to bear witness, equivalent. to testi(s) witness + -ficārī -fy
- Middle English testifyen 1350–1400
- 5.See corresponding entry in Unabridged indicate, show, signify, prove.
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