The quality or state of being avid; intense enthusiasm or keen desire.
From 'avid' (adjective) + suffix '-ness' (quality of), a common English pattern for turning adjectives into abstract nouns describing their inherent quality.
While 'avidness' and 'avidity' mean nearly the same thing, 'avidness' sounds more direct and English (using the Germanic suffix '-ness'), while 'avidity' sounds more formal (using the Latinate suffix '-ity').
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