Atavism

biology.

the reappearance in an individual of characteristics of some remote ancestor that have been absent in intervening generations.
an individual embodying such a reversion.

reversion to an earlier type; throwback.
historical examples

it must explain all the facts which const-tute what is known as atavism.
the making of species douglas dewar

i used the word ‘atavism’ to mean a reversion to the primitive.
measure for a loner james judson harmon

an atavism from “the old border riders” of scotland shone through the boy, and he took on quickly.
crooked trails frederic remington

can i explain, can anyone explain, the mysterious vagaries of atavism?
uncanny tales various

bohr was an atavism—they caught him trying to ‘take over’ there, and banished him.
man of many minds e. everett evans

altogether a good deal of nonsense has been written about atavism.
woman william j. robinson

these he “threw back” to his grandfather—not a fortunate ill-stration of the biological principle of atavism.
william the third h. d. traill

i would not omit to mention also the law of atavism, in this discussion of heredity.
what a young woman ought to know mary wood-allen

less marked cases set down to atavism may be instances merely of normal regression.
encyclopaedia britannica, 11th edition, volume 13, slice 3 various

for a short moment he hesitated but atavism and necessity were against him.
skippy bedelle owen johnson

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
n.

1833, from french atavisme, attested by 1820s, from latin atavus “ancestor, forefather,” from at- perhaps here meaning “beyond” + avus “grandfather,” from pie -awo- “adult male relative other than the father” (see uncle).

atavism at·a·vism (āt’ə-vĭz’əm)
n.
the appearance of characteristics that are presumed to have been present in some remote ancestor; reversion to an earlier biological type.
at’a·vist n.
at’a·vis’tic adj.
at’a·vis’ti·cal·ly adv.