(1):

(n.) That which is expired; matter breathed forth; that which is produced by breathing out, as a sound.

(2):

(n.) A coming to a close; cessation; extinction; termination; end.

(3):

(n.) The last emission of breath; death.

(4):

(n.) The act of expiring

(5):

(n.) Emission of volatile matter; exhalation.

(6):

(n.) The act or process of breathing out, or forcing air from the lungs through the nose or mouth; as, respiration consists of inspiration and expiration; - opposed to inspiration.