loin vs body part

loin and body part both are nouns.

Word	Noun	Adjective	Verb	Adverb
loin	Yes	No	No	No
body part	Yes	No	No	No

As nouns, body part is a hypernym of loin; that is, body part is a word with a broader meaning than loin:

loin: either side of the backbone between the hipbone and the ribs in humans as well as quadrupeds
body part: any part of an organism such as an organ or extremity

loin (noun)	body part (noun)
either side of the backbone between the hipbone and the ribs in humans as well as quadrupeds	any part of an organism such as an organ or extremity
a cut of meat taken from the side and back of an animal between the ribs and the rump