Alyssum
Alyssum (ȧ*lis"sum) , noun
[New Latin, from Greek 'a`lysson, name of a plant, perh. from 'a priv. + ly`ssa raging madness.]
(Botany) A genus of cruciferous plants; madwort. The sweet alyssum (Alyssum maritimum), cultivated for bouquets, bears small, white, sweet-scented flowers.