Definition of water mint in US English:

water mint

noun

  • Any of several plants of the genus Mentha (family Lamiaceae (Labiatae)), having aromatic leaves and typically growing in or close to water; specifically M. aquatica of Eurasia and northern Africa, which has rounded clusters of pale purplish flowers.

Origin

Middle English; earliest use found in Pluteus. From water + mint.

Pronunciation

water mint

/ˈwɔːtə mɪnt/