any of a genus (Tanacetum) of plants of the composite family; esp., a poisonous weed (T. vulgare) with strong-smelling foliage and flat-topped clusters of small, yellow, rayless flower heads
See tansy in American Heritage Dictionary 4
(tănˈzē)
nounpl.tan·sies
Any of several plants of the genus Tanacetum, especially T. vulgare, native to Eurasia, having corymbs of buttonlike yellow flower heads and aromatic, pinnately dissected leaves that are sometimes used medicinally.