tenesmus vs muscle spasm

tenesmus and muscle spasm both are nouns.

Word	Noun	Adjective	Verb	Adverb
tenesmus	Yes	No	No	No
muscle spasm	Yes	No	No	No

As nouns, muscle spasm is a hypernym of tenesmus; that is, muscle spasm is a word with a broader meaning than tenesmus:

tenesmus: painful spasm of the anal sphincter along with an urgent desire to defecate without the significant production of feces; associated with irritable bowel syndrome
muscle spasm: a painful and involuntary muscular contraction

Other hypernyms of tenesmus include cramp, spasm.

tenesmus (noun)	muscle spasm (noun)
painful spasm of the anal sphincter along with an urgent desire to defecate without the significant production of feces; associated with irritable bowel syndrome	a painful and involuntary muscular contraction