lobe vs body part

lobe and body part both are nouns.

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

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

lobe (noun)	body part (noun)
a rounded projection that is part of a larger structure	any part of an organism such as an organ or extremity
(anatomy) a somewhat rounded subdivision of a bodily organ or part
the enhanced response of an antenna in a given direction as indicated by a loop in its radiation pattern
(botany) a part into which a leaf is divided