"breathe deeply and rapidly," 1931, from hyper- "over, exceedingly, to excess" + ventilate in a medical sense. Perhaps a back-formation from ventilation. Earlier in a transitive sense, "to ventilate thoroughly" (1920 of lungs, 1906 of rooms). Related: Hyperventilated; hyperventilating.
updated on September 24, 2015
Dictionary entries near hyperventilate