fecal matter vs turd

fecal matter and turd both are nouns.

Word	Noun	Adjective	Verb	Adverb
fecal matter	Yes	No	No	No
turd	Yes	No	No	No

As nouns, turd is a hyponym of fecal matter; that is, turd is a word with a more specific, narrower meaning than fecal matter:

Other hyponyms of fecal matter include dog do, dog shit, dog turd, doggy do, crap, dirt, poop, shit, shite, droppings, dung, muck, meconium, melaena, melena.

fecal matter (noun)	turd (noun)
solid excretory product evacuated from the bowels	obscene terms for feces