I. ˈad.əˌvizəm, ˈatəˌ- noun
( -s )
Etymology: French atavisme, from Latin atavus ancestor, grandfather's or grandmother's great-grandfather (perhaps from atta daddy + avus grandfather) + French -isme -ism
1. : recurrence in an organism or in any of its parts of a form typical of ancestors more remote than the parents usually due to recombination of ancestral genes
2. : an individual or character manifesting atavism : throwback , reversion
he was a magnificent atavism , a man so purely primitive — Jack London
II. noun
: recurrence of or reversion to a past style, manner, outlook, approach, or activity
architectural atavism