teasel

1a :  an Old World prickly herb (Dipsacus fullonum of the family Dipsacaceae, the teasel family) with flower heads that are covered with stiff hooked bracts and were used especially formerly in the woolen industry —called also fuller's teaselb :  a plant of the same genus as the teasel

2a :  a flower head of the fuller's teasel used when dried to raise a nap on woolen clothb :  a wire substitute for the teasel