scenarist vs writer

scenarist and writer both are nouns.

Word	Noun	Adjective	Verb	Adverb
scenarist	Yes	No	No	No
writer	Yes	No	No	No

As nouns, writer is a hypernym of scenarist; that is, writer is a word with a broader meaning than scenarist:

scenarist: a writer of screenplays
writer: writes (books or stories or articles or the like) professionally (for pay)

Other hypernyms of scenarist include author.

scenarist (noun)	writer (noun)
a writer of screenplays	writes (books or stories or articles or the like) professionally (for pay)
	a person who is able to write and has written something