atavistical

Adjective

atavistical (comparative more atavistical, superlative most atavistical)

1. Atavistic.
   • Atavistical reversions: In biology the restoration of structural characters which have long been lost or obscured; near return to an original type occurring through partly modified descendants; resemblance to remote ancestors or progenitors; partial return, through hereditary influences, of remote...1914, Francis H. Buzzacott, Mystery of the Sexes: Secrets of Past and Future Human Creationism, page 39
   • All the legendry, of course, white and Indian alike, died down during the nineteenth century, except for occasional atavistical flareups.1931, H. P. Lovecraft, chapter 1, in The Whisperer in Darkness