1. The reappearance of a characteristic in an organism after several generations of absence.
2. An individual or a part that exhibits atavism. Also called throwback.
3. The return of a trait or recurrence of previous behavior after a period of absence.
[French atavisme, from Latin atavus, ancestor : atta, father + avus, grandfather; see awo- in the Appendix of Indo-European roots.]
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