vouch (n.)
formal statement, attestation, express declaration
H8 I.i.157[Buckingham to Norfolk, of declaring Wolsey treasonous] I'll ... make my vouch as strong / As shore of rock
MM II.iv.156[Angelo to Isabella] My vouch against you, and my place i'th' state, / Will ... your accusation overweigh
SHAKESPEARE'S WORDS © 2018 DAVID CRYSTAL & BEN CRYSTAL