vouche

(transitive) To affirm or warrant the correctness or truth of (something); also, to affirm or warrant (the truth of an assertion or statement).

(transitive) To cite or rely on (an authority, a written work, etc.) in support of one's actions or opinions.

(transitive) To back, confirm, or support (someone or something) with credible evidence or proof.

(transitive) To bear witness or testify to the nature or qualities (of someone or something).

To express confidence in or take responsibility for (the correctness or truth of) something.

(transitive) To call on (someone) to be a witness to something.

To bear witness or testify; to guarantee or sponsor.

To provide evidence or proof.

(transitive) (law) In full vouch to warrant or vouch to warranty: to summon (someone) into court to establish a warranty of title to land.

(transitive) (law) Followed by over: of a vouchee (a person summoned to court to establish a warranty of title): to summon (someone) to court in their place.

(intransitive) Often followed by for.

(transitive) (archaic) Synonym of vouchsafe (“to condescendingly or graciously give or grant (something)”).

(transitive) (archaic or obsolete) To assert, aver, or declare (something).

(transitive) (law) (obsolete) To guarantee legal title (to something).

(archaic or obsolete) An assertion, a declaration; also, a formal attestation or warrant of the correctness or truth of something.