Mephitic \Me*phit"ic\, Mephitical \Me*phit"ic*al\, a. [L. mephiticus, fr. mephitis mephitis: cf. F. m['e]phitique.]

1. Tending to destroy life; poisonous; noxious; as, mephitic exhalations; mephitic regions.

2. Offensive to the smell; as, mephitic odors.

Mephitic air (Chem.), carbon dioxide; -- so called because of its deadly suffocating power. See Carbonic acid, under Carbonic.

Source: Webster's Revised Unabridged Dictionary (1913)