largemouthed bass vs largemouth bass

largemouthed bass and largemouth bass both are nouns.

Word	Noun	Adjective	Verb	Adverb
largemouthed bass	Yes	No	No	No
largemouth bass	Yes	No	No	No

As nouns, largemouthed bass and largemouth bass are synonyms defined as:

largemouthed bass and largemouth bass: a large black bass; the angle of the jaw falls behind the eye

Other synonyms of largemouthed bass include largemouth, largemouth black bass, largemouthed black bass, Micropterus salmoides.

largemouthed bass (noun)	largemouth bass (noun)
a large black bass; the angle of the jaw falls behind the eye	a large black bass; the angle of the jaw falls behind the eye
	flesh of largemouth bass