gamecock vs fighting cock

gamecock and fighting cock both are nouns.

Word	Noun	Adjective	Verb	Adverb
gamecock	Yes	No	No	No
fighting cock	Yes	No	No	No

As nouns, gamecock and fighting cock are synonyms defined as:

gamecock (noun)	fighting cock (noun)
a cock bred and trained for fighting	a cock bred and trained for fighting
someone who is a very fierce fighter