shitting vs evacuation

shitting and evacuation both are nouns.

Word	Noun	Adjective	Verb	Adverb
shitting	Yes	No	No	No
evacuation	Yes	No	No	No

As nouns, evacuation is a hypernym of shitting; that is, evacuation is a word with a broader meaning than shitting:

Other hypernyms of shitting include elimination, excreting, excretion, voiding.

shitting (noun)	evacuation (noun)
the elimination of fecal waste through the anus	the act of removing the contents of something
	the act of evacuating; leaving a place in an orderly fashion; especially for protection
	the bodily process of discharging waste matter