From Longman Dictionary of Contemporary Englishhairdryerhair‧dry‧er, hairdrier /ˈheəˌdraɪə $ ˈherˌdraɪər/ ●●○ noun [countable] 
DCBa machine that blows out hot air for drying hair SYN blow-dryer
DCBa machine that blows out hot air for drying hair SYN blow-dryerExamples from the Corpus
hairdryer• Let your hair dry naturally instead of using a hairdryer.• She was wearing a quilted housecoat, and in her hand was a hairdryer.• All bedrooms have private facilities, television, telephone and hairdryer.• The premier plus rooms have mini bars, hairdryers and trouser presses.• And the best way to dry long hair is with a hooded hairdryer.• Constant use of hairdryers and heated rollers takes its toll.• By introducing their Reverso hairdryer earlier this year, BaByliss have taken diffuser drying one step ahead.• Rooms vary in size and come equipped with hairdryers, television and telephone. 