An Expiration

1. The act of expiring.
2. The act or process of breathing out, or forcing air from the lungs through the nose or mouth
3. Emission of volatile matter; exhalation.
4. (euphemistic) The last emission of breath; death.
5. A cessation, extinction, ending
6. That which is produced by breathing out, as a sound.

In most senses, mainly US; UK equivalent is expiry.

(breathing out): exhalation

(cessation): termination, end

(breathing out): inspiration, inhalation