defecation vs shit

defecation and shit both are nouns.

Word	Noun	Adjective	Verb	Adverb
defecation	Yes	No	No	No
shit	Yes	No	Yes	No

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

Other hyponyms of defecation include bm, bowel movement, movement, haematochezia, hematochezia, dump, urochesia, urochezia.

defecation (noun)	shit (noun)
the elimination of fecal waste through the anus	something of little value
	Obscene word for unacceptable behavior
	insulting terms of address for people who are stupid or irritating or ridiculous
	a coarse term for defecation
	a small worthless amount
	obscene terms for feces

defecation (verb)	shit (verb)
	have a bowel movement
	give away information about somebody