hang-up vs obstruction

hang-up and obstruction both are nouns.

Word	Noun	Adjective	Verb	Adverb
hang-up	Yes	No	No	No
obstruction	Yes	No	No	No

As nouns, obstruction is a hypernym of hang-up; that is, obstruction is a word with a broader meaning than hang-up:

hang-up: an unforeseen obstacle
obstruction: something immaterial that stands in the way and must be circumvented or surmounted

Other hypernyms of hang-up include obstacle.

hang-up (noun)	obstruction (noun)
an unforeseen obstacle	getting in someone's way
an emotional preoccupation	the act of obstructing
	any structure that makes progress difficult
	something immaterial that stands in the way and must be circumvented or surmounted
	the physical condition of blocking or filling a passage with an obstruction