emesis vs reflex action

emesis and reflex action both are nouns.

Word	Noun	Adjective	Verb	Adverb
emesis	Yes	No	No	No
reflex action	Yes	No	No	No

As nouns, reflex action is a hypernym of emesis; that is, reflex action is a word with a broader meaning than emesis:

emesis: the reflex act of ejecting the contents of the stomach through the mouth
reflex action: an automatic instinctive unlearned reaction to a stimulus

emesis (noun)	reflex action (noun)
the reflex act of ejecting the contents of the stomach through the mouth	an automatic instinctive unlearned reaction to a stimulus