pendulum vs bob

pendulum and bob both are nouns.

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

pendulum (noun)	bob (noun)
an apparatus consisting of an object mounted so that it swings freely under the influence of gravity	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

pendulum (verb)	bob (verb)
	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