pennywort
Concise Oxford English Dictionary © 2008 Oxford University Press:
pennywort /ˈpɛnɪwəːt/
▶noun a plant with small rounded leaves, growing in crevices or marshy places. [Umbilicus rupestris (wall pennywort) and Hydrocotyle vulgaris (marsh or water pennywort).]
'pennywort' also found in these Oxford entries:

