loosestrife
Concise Oxford English Dictionary © 2008 Oxford University Press:
loosestrife /ˈluːsˌstrʌɪf/
▶noun a waterside plant with a tall upright spike of flowers. [Lythrum salicaria (purple loosestrife), Lysimachia vulgaris (yellow loosestrife), and related plants.]
'loosestrife' also found in these Oxford entries:

