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Webster 1913 Edition
Oaf
1.
Originally, an elf’s child; a changeling left by fairies or goblins; hence, a deformed or foolish child; a simpleton; an idiot.
Webster 1828 Edition
Oaf
OAF
,Noun.
1.
A changeling; a foolish child left by fairies in the place of another.2.
A dolt; an idiot; a blockhead.