Definition of mutationist in English:

mutationist

Pronunciation /mjuːˈteɪʃ(ə)nɪst/ /mjuːˈteɪʃənɪst/

noun

historical Biology
  • An advocate of mutation theory; a person who believes that evolution is caused primarily by mutation. Also attributive or as adjective Compare "selectionist".

Origin

Early 20th century; earliest use found in Science. From mutation + -ist.