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inhalation vs. exhalation

inhalation

[in-huh-ley-shuhn] / ˌɪn həˈleɪ ʃən /

noun

an act or instance of inhaling.
an inhalant.

exhalation

[eks-huh-ley-shuhn, ek-suh-] / ˌɛks həˈleɪ ʃən, ˌɛk sə- /

noun

the act of exhaling.
something that is exhaled; vapor; emanation.