Gallus gallus vs capon

Gallus gallus and capon both are nouns.

Word	Noun	Adjective	Verb	Adverb
Gallus gallus	Yes	No	No	No
capon	Yes	No	No	No

As nouns, capon is a hyponym of Gallus gallus; that is, capon is a word with a more specific, narrower meaning than Gallus gallus:

Gallus gallus: a domestic fowl bred for flesh or eggs; believed to have been developed from the red jungle fowl
capon: castrated male chicken

Other hyponyms of Gallus gallus include biddy, chick, cock, rooster, biddy, hen, spring chicken, Rhode Island red, Dominick, Dominique, Orpington.

Gallus gallus (noun)	capon (noun)
a jungle fowl of southeastern Asia that is considered ancestral to the domestic fowl	castrated male chicken
a domestic fowl bred for flesh or eggs; believed to have been developed from the red jungle fowl	flesh of a castrated male chicken