'Inhalation' definitions:

Definition of 'inhalation'

(from WordNet)
noun
The act of inhaling; the drawing in of air (or other gases) as in breathing [syn: inhalation, inspiration, aspiration, intake, breathing in]
noun
A medication to be taken by inhaling it [syn: inhalant, inhalation]

Definition of 'Inhalation'

From: GCIDE
  • Inhalation \In`ha*la"tion\, n. [Cf. F. inhalation.] The act of inhaling; also, that which is inhaled. [1913 Webster]