saw-wort

from The Century Dictionary.

• noun The button-snakeroot, Laciniaria spicata.
• noun A plant of the Old World genus Serratula, especially S. tinctoria, whose foliage yields a yellow dye. The name is derived from the sharp serration of the leaves. Species of Saussurea are also so called.

from the GNU version of the Collaborative International Dictionary of English.

• noun (Bot.) Any plant of the composite genus Serratula; -- so named from the serrated leaves of most of the species.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun European perennial whose serrate leaves yield a yellow dye