skidder vs tractor

skidder and tractor both are nouns.

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

As nouns, tractor is a hypernym of skidder; that is, tractor is a word with a broader meaning than skidder:

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

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