spasm vs laryngismus

spasm and laryngismus both are nouns.

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

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

spasm: (pathology) sudden constriction of a hollow organ (as a blood vessel)
laryngismus: laryngeal spasm caused by the sudden contraction of laryngeal muscles

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

spasm (noun)	laryngismus (noun)
(pathology) sudden constriction of a hollow organ (as a blood vessel)	laryngeal spasm caused by the sudden contraction of laryngeal muscles
a painful and involuntary muscular contraction