Meaning

noun the metabolic processes whereby certain organisms obtain energy from organic molecules; processes that take place in the cells and tissues during which energy is released and carbon dioxide is produce

noun a single complete act of breathing in and out

noun the bodily process of inhalation and exhalation; the process of taking in oxygen from inhaled air and releasing carbon dioxide by exhalation

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

Etymology from Wiktionary, CC BY-SA 3.0