To decline or fail to do something promised; to break one's word.
To avert (one's eyes or a gaze).
To pull (something) back or back inside.
Of something said or written (such as published academic work): to take back or withdraw.
To draw (an extended body part) back into the body.
To take back or withdraw (something that has been said or written); to disavow, to repudiate.
Originally in chess and now in other games as well: to take back or undo (a move); specifically (card games) to take back or withdraw (a card which has been played).
To break or fail to keep (a promise, etc.); to renege.
To draw back; to draw up; to withdraw.
To pronounce (a sound, especially a vowel) farther to the back of the vocal tract.
To cancel or take back (something, such as an edict or a favour or grant previously bestowed); to rescind, to revoke.
To assert, aver, or declare (something).
To provide evidence or proof.
To back, confirm, or support (someone or something) with credible evidence or proof.
To call on (someone) to be a witness to something.
To affirm or warrant the correctness or truth of (something); also, to affirm or warrant (the truth of an assertion or statement).
To bear witness or testify; to guarantee or sponsor.
To cite or rely on (an authority, a written work, etc.) in support of one's actions or opinions.
To bear witness or testify to the nature or qualities (of someone or something).
In full vouch to warrant or vouch to warranty: to summon (someone) into court to establish a warranty of title to land.
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.
To express confidence in or take responsibility for (the correctness or truth of) something.
An assertion, a declaration; also, a formal attestation or warrant of the correctness or truth of something.