tractor vs skidder

tractor and skidder both are nouns.

Word	Noun	Adjective	Verb	Adverb
tractor	Yes	No	No	No
skidder	Yes	No	No	No

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

tractor: a wheeled vehicle with large wheels; used in farming and other applications
skidder: a tractor used to haul logs over rough terrain

Other hyponyms of tractor include bulldozer, dozer.

tractor (noun)	skidder (noun)
a wheeled vehicle with large wheels; used in farming and other applications	a tractor used to haul logs over rough terrain
a truck that has a cab but no body; used for pulling large trailers or vans	a worker who uses a skid to move logs
	a person who slips or slides because of loss of traction