maturationist
/ˌmatʃʊˈreɪʃ(ə)nɪst/ /ˌmatʃʊˈreɪʃənɪst/ /ˌmatjʊˈreɪʃ(ə)nɪst/Psychology and Linguistics (chiefly North American )
noun
A person who believes that genetic factors are more important than environmental ones in determining a child's development, especially with regard to the acquisition of language.
adjective
Of, relating to, or characteristic of maturationists or their beliefs.
Origin
1960s; earliest use found in Canadian Medical Association Journal. From maturation + -ist.