Definify.com
Webster 1913 Edition
Avouch
A-vouch′
,Verb.
 T.
 [
imp. & p. p. 
Avouched 
([GREEK]); p. pr. & vb. n. 
Avouching
.] 1. 
To appeal to; to cite or claim as authority. 
[Obs.] 
They 
avouch 
many successions of authorities. Coke.
2. 
To maintain a just or true; to vouch for. 
We might be disposed to question its authenticity, it if were not 
avouched 
by the full evidence. Milman.
3. 
To declare or assert positively and as matter of fact; to affirm openly. 
If this which he 
avouches 
does appear. Shakespeare
Such antiquities could have been 
avouched 
for the Irish. Spenser.
4. 
To acknowledge deliberately; to admit; to confess; to sanction. 
Thou hast 
 avouched 
the Lord this day to be thy God. Deut. xxvi. 17.
A-vouch′
,Noun.
 Evidence; declaration. 
[Obs.] 
The sensible and true 
Of mine own eyes.
avouch
Of mine own eyes.
Shakespeare
Webster 1828 Edition
Avouch
AVOUCH'
,Verb.
T.
  1.
  To affirm; to declare or assert with positiveness.2.
  To produce or call in; to affirm in favor of, maintain or support.Such antiquities could be avouched for the Irish.
3.
  To maintain, vindicate or justify.AVOUCH'
,Noun.
  Definition 2025
avouch
avouch
English
Verb
avouch (third-person singular simple present avouches, present participle avouching, simple past and past participle avouched)
-  To declare freely and openly; to assert.
-  Shakespeare
- if this which he avouches does appear
 
 -  Spenser
- Such antiquities could have been avouched for the Irish.
 
 
 -  Shakespeare
 -  To acknowledge deliberately; to admit; to confess; to sanction.
-  Bible, Deuteronomy xxvi. 17
- Thou hast avouched the Lord this day to be thy God.
 
 
 -  Bible, Deuteronomy xxvi. 17
 -  To confirm or verify, to affirm the validity of.
-  Milman
- We might be disposed to question its authenticity, it if were not avouched by the full evidence.
 
 
 -  Milman
 -  To appeal to; to cite or claim as authority.
-  Edward Coke
- They avouch many successions of authorities.
 
 
 -  Edward Coke
 
Noun
avouch (uncountable)
-  (obsolete) evidence; declaration
-  Shakespeare
- The sensible and true avouch / Of mine own eyes.
 
 
 -  Shakespeare