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Definitions

testify

[tes-tuh-fahy] / ˈtɛs təˌfaɪ /
VERB
vouch for; give testimony
Synonyms
STRONGEST
announce argue assert declare depose indicate swear
STRONG
affirm attest bespeak betoken certify corroborate demonstrate depone evince mount prove show sing state warrant witness
WEAK
bear witness cross one's heart give evidence give facts give one's word make evident point to say so stand up for swear to swear up and down token
Antonyms
STRONGEST
conceal deny hide
STRONG
contradict discredit refute reject veto

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

As a statutory inquiry, expected to last three years, investigators will have more powers than previous investigations - such as requiring people to testify and release other forms of evidence, and a budget of £65m.

From BBC • Mar. 27, 2026

Gus must decide: Should she testify in Jean’s defense?

From The Wall Street Journal • Mar. 27, 2026

Kaley G.M., the 20-year-old plaintiff, arrived in court just before 10 a.m. wearing the same rose-colored maxi dress she’d donned to testify in February.

From Los Angeles Times • Mar. 25, 2026

District Judge Zahid Quraishi to unload on career prosecutors last Monday, throwing one out of the courtroom and ordering the “triumvirate” to testify under oath about their illegal leadership structure.

From Slate • Mar. 24, 2026

But it turned out that Kirby couldn’t testify, either.

From "Killers of the Flower Moon" by David Grann