Thatch (?), n. [OE. thak, AS. þæc a roof; akin to þeccean to cover, D. dak a roof, dekken to cover, G. dach a roof, decken 8cover, Icel. þak a roof, Sw. tak, Dan. tag, Lith. stōgas, Ir. teagh a house, Gael. teach, tigh, W. ty, L. tegere to cover, toga a toga, Gr. �, �, a roof, � to cover, Skr. sthag. Cf. Deck, Integument, Tile, Toga.] 1. Straw, rushes, or the like, used for making or covering the roofs of buildings, or of stacks of hay or grain.
2. (Bot.) A name in the West Indies for several kinds of palm, the leaves of which are used for thatching.
Thatch sparrow, the house sparrow.