weak part vs weak spot

weak part and weak spot both are nouns.

Word	Noun	Adjective	Verb	Adverb
weak part	Yes	No	No	No
weak spot	Yes	No	No	No

As nouns, weak part and weak spot are synonyms defined as:

Other synonyms of weak part include soft spot.

weak part (noun)	weak spot (noun)
a place of especial vulnerability	a place of especial vulnerability