In popular language grass means a short, green, ground covering or lawn, usually, but not necessarily, comprised of a "true grass" or grasses, called turf. See also pasture, grass (material).
In botany, grass refers to plants of the Family Poaceae. These are the true grasses. Plants that are not true grasses include: - China grass or remie or rhea (Boehmeria nivea), a nettle grown for bast fibers from the Family Urticaceae - Ditch grass or Widgeon grass (Ruppia maritima) in the Family Ruppiaceae - Fish grass (Cabomba caroliniana) - Mondo grass or lily turf (Ophiopogon japonicus), an Asian ornamental ground cover - Nut grass, a common lawn pest (Cyperus rotundus) in the Family Cyperaceae - Pepper grasses (Lipidium spp.) in the Family Brassicaceae - Saw grass, abundant in sub-tropical marshlands (Cladium spp.) in the Family Cyperaceae - Scurvy grass (Oxalis enneaphylla) from the Family Oxalidaceae - Seagrasses, including Eel grass - Sleeping grass (Mimosa pudica) a legume (Family Fabaceae) and lawn pest - Xyridaceae, known as the yellow-eyed grass family
