literary hack vs writer

literary hack and writer both are nouns.

Word	Noun	Adjective	Verb	Adverb
literary hack	Yes	No	No	No
writer	Yes	No	No	No

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

literary hack: a mediocre and disdained writer
writer: writes (books or stories or articles or the like) professionally (for pay)

Other hypernyms of literary hack include author.

literary hack (noun)	writer (noun)
a mediocre and disdained writer	writes (books or stories or articles or the like) professionally (for pay)
	a person who is able to write and has written something