bullfight vs novillada

bullfight and novillada both are nouns.

Word	Noun	Adjective	Verb	Adverb
bullfight	Yes	No	No	No
novillada	Yes	No	No	No

As nouns, novillada is a hyponym of bullfight; that is, novillada is a word with a more specific, narrower meaning than bullfight:

bullfight: a Spanish or Portuguese or Latin American spectacle; a matador baits and (usually) kills a bull in an arena before many spectators
novillada: a bullfight in which the bulls are less than four years old

bullfight (noun)	novillada (noun)
a Spanish or Portuguese or Latin American spectacle; a matador baits and (usually) kills a bull in an arena before many spectators	a bullfight in which the bulls are less than four years old