tail end vs body part

tail end and body part both are nouns.

Word	Noun	Adjective	Verb	Adverb
tail end	Yes	No	No	No
body part	Yes	No	No	No

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

tail end (noun)	body part (noun)
the fleshy part of the human body that you sit on	any part of an organism such as an organ or extremity
any projection that resembles the tail of an animal
the time of the last part of something