rhymer vs author

rhymer and author both are nouns.

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

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

rhymer: a writer who composes rhymes; a maker of poor verses (usually used as terms of contempt for minor or inferior poets)
author: writes (books or stories or articles or the like) professionally (for pay)

Other hypernyms of rhymer include writer.

rhymer (noun)	author (noun)
a writer who composes rhymes; a maker of poor verses (usually used as terms of contempt for minor or inferior poets)	writes (books or stories or articles or the like) professionally (for pay)
	someone who originates or causes or initiates something

rhymer (verb)	author (verb)
	be the author of