lyricist vs author

lyricist and author both are nouns.

Word	Noun	Adjective	Verb	Adverb
lyricist	Yes	No	No	No
author	Yes	No	Yes	No

As nouns, author is a hypernym of lyricist; that is, author is a word with a broader meaning than lyricist:

lyricist: a person who writes the words for songs
author: writes (books or stories or articles or the like) professionally (for pay)

Other hypernyms of lyricist include writer.

lyricist (noun)	author (noun)
a person who writes the words for songs	writes (books or stories or articles or the like) professionally (for pay)
	someone who originates or causes or initiates something

lyricist (verb)	author (verb)
	be the author of