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Webster 1913 Edition
Atavism
At′a-vism
,Noun.
[L.
atavus
an ancestor, fr. avus
a grandfather.] 1.
(a)
The recurrence, or a tendency to a recurrence, of the original type of a species in the progeny of its varieties; resemblance to remote rather than to near ancestors; reversion to the original form.
(b)
(Biol.)
The recurrence of any peculiarity or disease of an ancestor in a subsequent generation, after an intermission for a generation or two.
Now and then there occur cases of what physiologists call
atavism
, or reversion to an ancestral type of character. J. Fiske