Old English compound: 'līm' (sticky substance/lime) + 'stān' (stone)—the rock that yields mortar.
A sedimentary rock composed mainly of calcium carbonate, formed from the accumulated shells and skeletons of marine organisms.
A compound of Old English 'līm' (lime, cement, birdlime) + 'stān' (stone). 'Lime' itself comes from Proto-Germanic *līmō from PIE *lei- (slimy, sticky), because burned limestone produces calcium oxide—the sticky substance used as mortar since antiquity. Key roots: *lei- (Proto-Indo-European: "slimy, sticky"), *stainaz (Proto-Germanic: "stone").