Watercress is a small plant with white flowers which grows in streams and pools. Its leaves taste hot and are eaten raw in salads.
watercress in British English
(ˈwɔːtəˌkrɛs)
noun
1.
an Old World plant, Nasturtium officinale, of clear ponds and streams, having pungent leaves that are used in salads and as a garnish: family Brassicaceae (crucifers)
2.
any of several similar or related plants
watercress in American English
(ˈwɔtərˌkrɛs; ˈwɑtərˌkrɛs)
noun
a white-flowered plant (Nasturtium officinale) of the crucifer family, growing generally in running water, as from springs: its leaves are used in salads, soups, etc.