Entry 2 senses · 2 variants Webster, 1913 Acerous · Ac·er·ous · IPA /ˈæs.əɹ.əs/ a. a. 01 a. Same as Acerose. 1. Same as Acerose. See: Acerose 02 a. Destitute of tentacles, as certain mollusks. 1. Destitute of tentacles, as certain mollusks.(Zool.)