earwitness
\EER-wit-nis\
noun
1. Law. a person who testifies or can testify to what he or she has heard.
Quotes
Such is the rather meagre account, as given by one ear-witness, of Patrick Henry's first speech in the Congress of 1774.
-- Moses Coit Tyler, American Statesmen: Patrick Henry, 1887
Origin
Earwitness entered English in the 1500s around the same time as eyewitness, however the latter is far more common.
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