dumbbell vs dummy

dumbbell and dummy both are nouns.

Word	Noun	Adjective	Verb	Adverb
dumbbell	Yes	No	No	No
dummy	Yes	Yes	Yes	No

As nouns, dumbbell and dummy are synonyms defined as:

Other synonyms of dumbbell include boob, booby, dope, pinhead.

dumbbell (noun)	dummy (noun)
an exercising weight; two spheres connected by a short bar that serves as a handle	a figure representing the human form
an ignorant or foolish person	a cartridge containing an explosive charge but no bullet
	an ignorant or foolish person
	a person who does not talk

dumbbell (adjective)	dummy (adjective)
	having the appearance of being real but lacking capacity to function

dumbbell (verb)	dummy (verb)
	make a dummy of