- rye grass, ryegrass - any of several annual or perennial Eurasian grasses
--1 is a kind of grass
--1 is a member of Lolium, genus Lolium
--1 has particulars:perennial ryegrass, English ryegrass, Lolium perenne; Italian ryegrass, Italian rye, Lolium multiflorum; darnel, tare, bearded darnel, cheat, Lolium temulentum