The definition of fain is glad or willing.
(adjective)An example of fain is a woman who is eager to marry her fiance.
See fain in Webster's New World College Dictionary
adjective
Origin: ME joyful, joyfully < OE fægen, glad, akin to ON feginn < IE base *pek-, to be satisfied > fair
adverb
See fain in American Heritage Dictionary 4
adverb
Origin:
Origin: Middle English
Origin: , from Old English fǽgen, joyful, glad
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