'Water arum' definitions:

Definition of 'water arum'

(from WordNet)
noun
Plant of wetlands and bogs of temperate regions having small greenish flowers partly enclosed in a white spathe and red berries [syn: wild calla, water arum, Calla palustris]

Definition of 'Water arum'

From: GCIDE
  • Water arum \Wa"ter a"rum\ (Bot.) An aroid herb (Calla palustris) having a white spathe. It is an inhabitant of the north temperate zone. [1913 Webster]