respiration

Etymology

From Middle English respiracioun, borrowed from Latin respīrātiō, respīrātiōnem.

noun

1. The process of inhaling and exhaling; breathing, breath.
   In the dead state all is apparently without motion. No agent within indicates design, intelligence, or foresight: there is no respiration; […] 1822, John Barclay, chapter I, in An Inquiry Into the Opinions, Ancient and Modern, Concerning Life and Organization, Edinburgh, London: Bell & Bradfute; Waugh & Innes; G. & W. B. Whittaker, section I, page 2
2. An act of breathing; a breath.
   Gowan snored, each respiration choking to a huddle fall, as though he would never breathe again. 1931, William Faulkner, Sanctuary, Vintage, published 1993, page 76
3. Any similar process in an organism that lacks lungs that exchanges gases with its environment.
4. The process by which cells obtain chemical energy by the consumption of oxygen and the release of carbon dioxide.