Entry 2 senses · 2 variants Webster, 1913 Aventine · Av·en·tine · IPA /ˈævəntaɪn/ a. n. 01 a. Pertaining to Mons Aventinus, one of the seven hills on which Rome stood. 1. Pertaining to Mons Aventinus, one of the seven hills on which Rome stood. 02 n. A post of security or defense. 1. A post of security or defense.[Poetic] “Into the castle's tower, The only Aventine that now is left him.” — Beau. & Fl.