Etymology
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respire (v.)

late 14c., respiren, "breathe, draw breath," from Old French respirer (12c.) and directly from Latin respirare "breathe again, breathe in and out," from re- "again" (see re-) + spirare "to breathe" (see spirit (n.)). Formerly also "to rest or enjoy relief after toil or exertion" (1590s). Related: Respired; respiring.

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respirator (n.)

1836, "an aid to breathing," originally a sort of metallic gauze mask fitted to the face by a wire frame and meant to keep out smoke, dust, and especially cold air; agent noun from respire. The word was later used of gas masks in World War I. As "machine to provide artificial respiration" from 1929.

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