liliopsid genus, monocot genus - genus of flowering plants having a single cotyledon (embryonic leaf) in the seed

arrow-grass family, family Juncaginaceae, family Scheuchzeriaceae, Juncaginaceae, Scheuchzeriaceae - a family of monocotyledonous bog herbs of order Naiadales

arrow grass, Triglochin maritima - tufted perennial found in shallow water or marshland; sometimes poisons livestock