mortalist /ˈmɔːtəlɪst/adjective 1noun 1forms 3 adjective1 •(historical) Pertaining to this doctrine of mortalism.Both Anabaptists and Familists sympathised with the ‘mortalist’ doctrine that the soul slept until the Day of Judgement […] — 1971 noun1 •Someone who believes that the soul is mortal like the body. formsmortalists · more mortalist · most mortalist