Definition of: thatch

(thach) noun
1. A covering of reeds, straw, etc., arranged on a roof so as to shed water.
2. Any of various palms whose leaves are used for thatching, especially those of the genera Thrinax and Sabal.
3. Any of certain tall, coarse American grasses (genus Spartina) of the northern Atlantic coasts.
—v.t. To cover with a thatch. [OE thæc cover]
—thatch′er noun
—thatch′y adjective