stoppage vs obstruction

stoppage and obstruction both are nouns.

Word	Noun	Adjective	Verb	Adverb
stoppage	Yes	No	No	No
obstruction	Yes	No	No	No

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

Other hypernyms of stoppage include impediment, impedimenta, obstructer, obstructor.

stoppage (noun)	obstruction (noun)
the act of stopping something	getting in someone's way
an obstruction in a pipe or tube	the act of obstructing
the state of inactivity following an interruption	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