grill vs oven broil

grill is a noun but oven broil is not a noun.

Word	Noun	Adjective	Verb	Adverb
grill	Yes	No	Yes	No
oven broil	No	No	Yes	No

As verbs, oven broil is a hyponym of grill; that is, oven broil is a word with a more specific, narrower meaning than grill:

Other hyponyms of grill include barbecue, barbeque, cook out, hibachi, broil.

grill (noun)	oven broil (noun)
a framework of metal bars used as a partition or a grate
a restaurant where food is cooked on a grill

grill (verb)	oven broil (verb)
cook over or under a grill	cook under a broiler
examine thoroughly