A person who avouches or asserts something; one who vouches for or guarantees something.
From avouch + -er (agent suffix meaning 'one who'). Following standard English noun formation, -er is added to verbs to create agent nouns.
An 'avoucher' in historical texts was often a witness or guarantor—someone whose word carried weight in society. The term reveals how crucial personal reputation was in a world before documentation and recordkeeping.
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