spasm vs retch

spasm and retch both are nouns.

Word	Noun	Adjective	Verb	Adverb
spasm	Yes	No	No	No
retch	Yes	No	Yes	No

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

spasm: (pathology) sudden constriction of a hollow organ (as a blood vessel)
retch: an involuntary spasm of ineffectual vomiting

Other hyponyms of spasm include bronchospasm, cardiospasm, heave, laryngismus.

spasm (noun)	retch (noun)
(pathology) sudden constriction of a hollow organ (as a blood vessel)	an involuntary spasm of ineffectual vomiting
a painful and involuntary muscular contraction

spasm (verb)	retch (verb)
	eject the contents of the stomach through the mouth
	make an unsuccessful effort to vomit; strain to vomit