atavism

[ at-uh-viz-uh m ]
/ ˈæt əˌvɪz əm /

noun

Biology.
  1. the reappearance in an individual of characteristics of some remote ancestor that have been absent in intervening generations.
  2. an individual embodying such a reversion.
reversion to an earlier type; throwback.

Origin of atavism

1825–35; < Latin atav(us) remote ancestor (at-, akin to atta familiar name for a grandfather + avus grandfather, forefather) + -ism

Related forms

at·a·vist, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for atavists

atavism

/ (ˈætəˌvɪzəm) /

noun

the recurrence in a plant or animal of certain primitive characteristics that were present in an ancestor but have not occurred in intermediate generations
reversion to a former or more primitive type

Derived Forms

atavist, nounatavic (əˈtævɪk), adjective

Word Origin for atavism

C19: from French atavisme, from Latin atavus strictly: great-grandfather's grandfather, probably from atta daddy + avus grandfather
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medicine definitions for atavists

atavism

[ ătə-vĭz′əm ]

n.

The appearance of characteristics that are presumed to have been present in some remote ancestor; reversion to an earlier biological type.

Related forms

ata•vist n.at′a•vistic adj.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.