late 14c., thecchen, from Old English þeccan "to cover, cover over, conceal," in late Old English specifically "cover the roof of a house," related to þæc "roof, thatching material," from Proto-Germanic *thakjan (source also of Old Saxon thekkian, Old Norse þekja, Old Frisian thekka, Middle Dutch decken, Dutch dekken, Old High German decchen, German decken "to cover"), from PIE root *(s)teg- "to cover."