hair dryer vs blow dryer

hair dryer and blow dryer both are nouns.

Word	Noun	Adjective	Verb	Adverb
hair dryer	Yes	No	No	No
blow dryer	Yes	No	No	No

As nouns, hair dryer and blow dryer are synonyms defined as:

hair dryer and blow dryer: a hand-held electric blower that can blow warm air onto the hair; used for styling hair

Other synonyms of hair dryer include blow drier, hair drier, hand blower.

hair dryer (noun)	blow dryer (noun)
a hand-held electric blower that can blow warm air onto the hair; used for styling hair	a hand-held electric blower that can blow warm air onto the hair; used for styling hair