Entry 2 senses · 2 variants Webster, 1913 Aroid · A·roid · IPA a. n. 01 a. Belonging to, or resembling, the Arum family of plants (Araceae). 1. Belonging to, or resembling, the Arum family of plants (Araceae).(Bot.) Syn. araceous 02 n. Any plant of the Arum family (Araceæ); -- have small flowers massed on a spadix surrounded by a large spathe. 1. Any plant of the Arum family (Araceæ); -- have small flowers massed on a spadix surrounded by a large spathe.(Bot.) Syn. arum