1.
[syn: flower-of-an-hour, flowers-of-an-hour, bladder ketmia, black-eyed Susan, Hibiscus trionum]
The Collaborative International Dictionary of English v.0.48:
flowers-of-an-hour \flowers-of-an-hour\ n.
An annual weedy herb (Hibiscus trionum) with ephemeral
yellow purple-eyed flowers, native to the Old World tropics
and naturalized as a weed in North America.
Syn: flower-of-an-hour, bladder ketmia, black-eyed Susan,
Hibiscus trionum.
[WordNet 1.5]
WordNet (r) 3.0 (2006):
flowers-of-an-hour
n 1: annual weedy herb with ephemeral yellow purple-eyed
flowers; Old World tropics; naturalized as a weed in North
America [syn: flower-of-an-hour, flowers-of-an-hour,
bladder ketmia, black-eyed Susan, Hibiscus trionum]