1725, "sound of the letter 'H'," especially at the beginning of a word, from Latin aspiratio "a breathing, exhalation; the pronunciation of the letter H" (see aspire).

"to pronounce with audible breath," 1700; perhaps a back-formation from aspiration (n.2), or from French aspirer or directly from Latin aspiratus, past participle of aspirare (see aspire). Related: Aspirated; aspirating.