Definition of avouch in English:

avouch

verb

[WITH OBJECT]archaic
  • Affirm or assert.

    • ‘Paulina and her friends being gone, I scarce could avouch that I had really seen them.’
    • ‘Ask Wall Street and they would enthusiastically avouch that they are quite up to the task - more than able and willing.’
    • ‘We might be disposed to question its authenticity, it if were not avouched by the full evidence.’
    assert, maintain, state, aver, affirm, contend, argue, insist, hold, profess, move, claim, allege, avow, vow, swear, attest, testify, certify
    View synonyms

Origin

Late 15th century: from Old French avochier, from Latin advocare ‘summon in defense’, from ad- ‘to’ + vocare ‘to call’.

Pronunciation

avouch

/əˈvaʊtʃ//əˈvouCH/