mignonette
Concise Oxford English Dictionary © 2008 Oxford University Press:
mignonette /ˌmɪnjəˈnɛt/
▶noun a plant with spikes of small fragrant greenish flowers. [Reseda lutea and related species.]
– origin C18: from Fr. mignonnette, dimin. of mignon ‘small and sweet’.
'mignonette' also found in these Oxford entries:

