1) Aroid 2) Liliopsid family 3) Monocot family 1) Aroid 
• (a.) Of or pertaining to an order of plants, of which the genus Arum is the type.
A·ra'ceous adjective [ Latin arum a genus of plants, from Greek ....] (Botany) Of or pertaining to an order of plants, of which the genus Arum is the type. 
belonging to the plant family Araceae. Cf. arum family.