hair drier vs blow dryer

hair drier and blow dryer both are nouns.

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

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

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

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

hair drier (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