obstruction vs stalling

obstruction and stalling both are nouns.

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

As nouns, stalling is a hyponym of obstruction; that is, stalling is a word with a more specific, narrower meaning than obstruction:

Other hyponyms of obstruction include blockage, closure, occlusion, stall, obstruction of justice.

obstruction (noun)	stalling (noun)
getting in someone's way	a tactic used to mislead or delay
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