sled vs bob

sled and bob both are nouns.

Word	Noun	Adjective	Verb	Adverb
sled	Yes	No	Yes	No
bob	Yes	No	Yes	No

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

sled: a vehicle mounted on runners and pulled by horses or dogs; for transportation over snow
bob: a long racing sled (for 2 or more people) with a steering mechanism

Other hyponyms of sled include bobsled, bobsleigh, bobsled, bobsleigh, dog sled, dog sleigh, dogsled, luge, pung, toboggan.

As verbs, bob is a hyponym of sled; that is, bob is a word with a more specific, narrower meaning than sled:

Other hyponyms of sled include dogsled, mush, bobsled, luge, toboggan.

sled (noun)	bob (noun)
a vehicle mounted on runners and pulled by horses or dogs; for transportation over snow	a short abrupt inclination (as of the head)
	a short or shortened tail of certain animals
	a small float usually made of cork; attached to a fishing line
	a hanging weight, especially a metal ball on a string
	a long racing sled (for 2 or more people) with a steering mechanism
	a hair style for women and children; a short haircut all around
	a former monetary unit in Great Britain

sled (verb)	bob (verb)
ride (on) a sled	cut hair in the style of a bob
	make a curtsy; usually done only by girls and women; as a sign of respect
	remove or shorten the tail of an animal
	move up and down repeatedly in a quick, short movement
	ride a bobsled