Variant of thack, from Old English þæċ (“roof-covering”), from Proto-Germanic *þaką (“covering”), from (o-grade of) Proto-Indo-European *teg- (“cover”). Cognate with Icelandic þak, Dutch dak, German Dach, Swedish tak, Danish tag; and with Latin toga, Albanian thak (“awn, beard, pin, peg, tassel, fringe”), Lithuanian stogas (“roof”).
- Straw, rushes, or the like, used for making or covering the roofs of buildings, or of stacks of hay or grain.
- A name in the West Indies for several kinds of palm, the leaves of which are used for thatching.
- A buildup of cut grass, stolons or other material on the soil in a lawn.
- (Straw for covering roofs or stacks): haulm
- To cover the roof with straw, reed, leaves, etc.