gin vs cotton gin

gin and cotton gin both are nouns.

Word	Noun	Adjective	Verb	Adverb
gin	Yes	No	Yes	No
cotton gin	Yes	No	No	No

As nouns, gin and cotton gin are synonyms defined as:

gin and cotton gin: a machine that separates the seeds from raw cotton fibers

gin (noun)	cotton gin (noun)
a form of rummy in which a player can go out if the cards remaining in their hand total less than 10 points	a machine that separates the seeds from raw cotton fibers
a machine that separates the seeds from raw cotton fibers
a trap for birds or small mammals; often has a slip noose
strong liquor flavored with juniper berries

gin (verb)	cotton gin (verb)
trap with a snare
separate the seeds from (cotton) with a cotton gin