water arum

noun
  1. an aquatic arum plant, Calla palustris, of the North Temperate Zone, having heart-shaped leaves, tiny green flowers, and red berries.

Origin of water arum

An Americanism dating back to 1810–20
Also called wild calla.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018