stoppage vs logjam

stoppage and logjam both are nouns.

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

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

Other hyponyms of stoppage include countercheck.

stoppage (noun)	logjam (noun)
the act of stopping something	an immovable mass of logs blocking a river
an obstruction in a pipe or tube	any stoppage attributable to unusual activity
the state of inactivity following an interruption