[1] : The Collaborative International Dictionary of English v.0.48

avouch \avouch"\, v. t. imp.  p. p. avouched ?; p. pr. 
   vb. n. avouching. of. avochier, ll. advocare to recognize
   the existence of a thing, to advocate, fr. l. advocare to
   call to; ad + vocare to call. cf. avow to declare,
   advocate, and see vouch, v. t.
   1. to appeal to; to cite or claim as authority. obs.
      1913 webster

            they avouch many successions of authorities. --coke.
      1913 webster

   2. to maintain a just or true; to vouch for.
      1913 webster

            we might be disposed to question its authenticity,
            it if were not avouched by the full evidence.
                                                  --milman.
      1913 webster

   3. to declare or assert positively and as matter of fact; to
      affirm openly.
      1913 webster

            if this which he avouches does appear. --shak.
      1913 webster

            such antiquities could have been avouched for the
            irish.                                --spenser.
      1913 webster

   4. to acknowledge deliberately; to admit; to confess; to
      sanction.
      1913 webster

            thou hast avouched the lord this day to be thy god.
                                                  --deut. xxvi.
                                                  17.
      1913 webster
see also:
avouched avouching avow advocate vouch 

[2] : The Collaborative International Dictionary of English v.0.48

avouch \avouch"\, n.
   evidence; declaration. obs.
   1913 webster

         the sensible and true avouch
         of mine own eyes.                        --shak.
   1913 webster

[3] : WordNet (r) 2.0

avouch
     v : admit openly and bluntly; make no bones about syn: avow
         ant: disavow
see also:
avow disavow 

[4] : Moby Thesaurus II by Grady Ward, 1.0

66 moby thesaurus words for "avouch":
   acknowledge, admit, affirm, allege, announce, annunciate, argue,
   assert, assever, asseverate, assure, attest, aver, avow,
   bear witness, certify, confess, confirm, contend, corroborate,
   countersign, declare, depone, depose, disclose, enunciate, express,
   express the belief, give evidence, guarantee, have, hold, insist,
   issue a manifesto, lay down, maintain, make a promise, manifesto,
   own, pledge, plight, predicate, proclaim, profess, promise,
   pronounce, protest, put, put it, say, set down, speak, speak out,
   speak up, stand for, stand on, state, submit, swear, testify,
   troth, underwrite, vouch, vow, warrant, witness

Avouch >> A Words
Avouch, definition of term: Avouch
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