squirm vs writhe

squirm is a noun but writhe is not a noun.

Word	Noun	Adjective	Verb	Adverb
squirm	Yes	No	Yes	No
writhe	No	No	Yes	No

As verbs, squirm and writhe are synonyms defined as:

squirm and writhe: to move in a twisting or contorted motion, (especially when struggling)

Other synonyms of squirm include twist, worm, wrestle, wriggle.

squirm (noun)	writhe (noun)
the act of wiggling

squirm (verb)	writhe (verb)
to move in a twisting or contorted motion, (especially when struggling)	to move in a twisting or contorted motion, (especially when struggling)