c.1300, "immediate influence of God or a god," especially that under which the holy books were written, from Old French inspiracion "inhaling, breathing in; inspiration," from Late Latin inspirationem (nominative inspiratio), noun of action from past participle stem of Latin inspirare "inspire, inflame, blow into," from in- "in" (see in-(2)) + spirare "to breathe" (see spirit). Literal sense "act of inhaling" attested in English from 1560s. Meaning "one who inspires others" is attested by 1867.