any of a number of plants with rounded leaves, in particular.
(wall pennywort) a small Eurasian plant that grows in crevices (Umbilicus rupestris, family Crassulaceae).Also called cotyledon or navelwort (marsh or water pennywort) a small creeping or floating plant of marshy places (Hydrocotyle vulgaris, family Umbelliferae).Also called navelwort
pennywort in other Oxford dictionaries
Definition of pennywort in the US English dictionary