One that inhales: an avid inhaler of aromatic pipe smoke.
A device that produces a vapor to ease breathing or is used to medicate by inhalation, especially a small nasal applicator containing a volatile medicament. Also called inhalator.
res·pi·ra·tor (rěs'pə-rā'tər) n.
A device that supplies oxygen or a mixture of oxygen and carbon dioxide for breathing, used especially in artificial respiration. Also called inhalator.
A screenlike device worn over the mouth or nose or both to protect the respiratory tract.
Main Entry: in·ha·la·tor Pronunciation: 'in-(h)&-"lAt-&r, 'in-&l-"At- Function: noun : a device providing amixture of oxygen and carbon dioxide for breathing that is used especially in conjunction with artificial respiration —compare INHALER
[in-huh-ley-ter] 
həˌleɪ