meteorologist vs specialiser

meteorologist and specialiser both are nouns.

Word	Noun	Adjective	Verb	Adverb
meteorologist	Yes	No	No	No
specialiser	Yes	No	No	No

As nouns, specialiser is a hypernym of meteorologist; that is, specialiser is a word with a broader meaning than meteorologist:

meteorologist: a specialist who studies processes in the earth's atmosphere that cause weather conditions
specialiser: an expert who is devoted to one occupation or branch of learning

Other hypernyms of meteorologist include specialist, specializer.

meteorologist (noun)	specialiser (noun)
a specialist who studies processes in the earth's atmosphere that cause weather conditions	an expert who is devoted to one occupation or branch of learning