noun
expiration
The act of breathing air out.
During quiet expiration, the diaphragm relaxes and air leaves the lungs.
Etymology
The Latin verb means to breathe out. This physiological sense of expiration preserves that literal action, naming the outward phase of breathing.
More examples
- The therapist asks her to make each expiration slow and steady.
- Expiration through pursed lips helps him control his breathing.
- The monitor records both inspiration and expiration.
Forms
expiration · expirations
expiratory adjective — Relating to breathing air out.
Similar words
- exhalation
- More common outside technical descriptions of the breathing cycle.
- exhaling
- Emphasizes the action rather than a phase of breathing.