behaviourist vs psychologist

behaviourist and psychologist both are nouns.

Word	Noun	Adjective	Verb	Adverb
behaviourist	Yes	Yes	No	No
psychologist	Yes	No	No	No

As nouns, psychologist is a hypernym of behaviourist; that is, psychologist is a word with a broader meaning than behaviourist:

behaviourist (noun)	psychologist (noun)
a psychologist who subscribes to behaviorism	a scientist trained in psychology

behaviourist (adjective)	psychologist (adjective)
of or relating to behaviorism