Merriam-Webster Collegiate Dictionary - briar

 I. noun  also brier  Etymology: Middle English brere, from Old English brer  Date: 15th century a plant (as a rose, blackberry, or greenbrier) having a usually woody and thorny or prickly stem; also a mass or twig of these  • ~y adjective  II. noun  Etymology: short for ~ pipe, from ~ wood of the European heath, from French bruyere heath, from Middle French bruiere, from Vulgar Latin *brucaria, from Late Latin brucus heather, of Celtic origin; akin to Old Irish froech heather; akin to Greek ereike heather  Date: 1882 a tobacco pipe made from the root or stem of a European heath (Erica arborea)