reversion

noun 0.661

vestigial

noun 0.610

reversionary

noun 0.584

archaism

noun 0.576

retrogression

noun 0.571

revertant

noun 0.561

retrogressive

noun 0.554

reliction

noun 0.545

retrogress

noun 0.539

plesiomorphy

noun 0.538

adaptationism

noun 0.536

reincarnation

noun 0.535

palingenesis

noun 0.535

primitivism

noun 0.532

ancestor

noun 0.531

archaic

noun 0.527

abiotrophy

noun 0.526

revenant

noun 0.524

vestige

noun 0.523

savagism

noun 0.522

autapomorphy

noun 0.520

anaplasia

noun 0.517

ancestry

noun 0.516

resurgence

noun 0.515

reemergence

noun 0.513

anachronism

noun 0.510

primitiveness

noun 0.510

living fossil

noun 0.509

vestigium

noun 0.508

ontology

noun 0.508

atrophy

noun 0.507

revivalism

noun 0.507

revert

noun 0.506

reminiscence

noun 0.505

recessiveness

noun 0.505

rebirth

noun 0.505

regress

noun 0.505

ataxin

noun 0.503

common ancestor

noun 0.503

ancestress

noun 0.502

regression

noun 0.502

evolutionism

noun 0.502

eternal return

noun 0.502

recrudescence

noun 0.501