Entry 1 sense Webster, 1913 Intoxicant · In·tox·i·cant · IPA /ɪnˈtɒksɪk(ə)nt/ 01 n. That which intoxicates; an intoxicating agent; as, alcohol, opium, and laughing gas are intoxicants. 1. That which intoxicates; an intoxicating agent; as, alcohol, opium, and laughing gas are intoxicants.