vibrator vs mechanical device

vibrator and mechanical device both are nouns.

Word	Noun	Adjective	Verb	Adverb
vibrator	Yes	No	No	No
mechanical device	Yes	No	No	No

As nouns, mechanical device is a hypernym of vibrator; that is, mechanical device is a word with a broader meaning than vibrator:

vibrator: mechanical device that produces vibratory motion; used for massage
mechanical device: mechanism consisting of a device that works on mechanical principles

As nouns, mechanical device is a hypernym of vibrator; that is, mechanical device is a word with a broader meaning than vibrator:

vibrator: a mechanical device that vibrates
mechanical device: mechanism consisting of a device that works on mechanical principles

vibrator (noun)	mechanical device (noun)
mechanical device that produces vibratory motion; used for massage	mechanism consisting of a device that works on mechanical principles
a mechanical device that vibrates