dead axle vs axletree

dead axle and axletree both are nouns.

Word	Noun	Adjective	Verb	Adverb
dead axle	Yes	No	No	No
axletree	Yes	No	No	No

As nouns, axletree is a hyponym of dead axle; that is, axletree is a word with a more specific, narrower meaning than dead axle:

dead axle: an axle that carries a wheel but without power to drive it
axletree: a dead axle on a carriage or wagon that has terminal spindles on which the wheels revolve

dead axle (noun)	axletree (noun)
an axle that carries a wheel but without power to drive it	a dead axle on a carriage or wagon that has terminal spindles on which the wheels revolve