avouch

Avouch is a verb meaning to affirm the truth of something, to assert or declare, and to acknowledge the existence or validity of something. It can also mean to vouch for someone's character or reliability, or to acknowledge responsibility for something. The term is formal or literary in tone and is less common in everyday speech.

Etymology: The word derives from Middle English, borrowed from Old French avouchier or avouer, related to the verb avouer “to confess” and cognate with the modern English avow and vouch. The sense of making a positive assertion or defense developed in legal and rhetorical usage.

Usage: In contemporary English, avouch tends to be formal or archaic, often appearing in legal, historical, or literary contexts. It is used with clauses such as that or for: “She avouched that the report was accurate,” or “He avouched the child as his own.” It can also mean to acknowledge responsibility for something or to voucha for someone’s character or reliability, as in “I avouch him as a trustworthy witness.” In older legal language, to avouch could mean to acknowledge paternity or ownership.

See also: avow, vouch, attest, certify.