Real Dictionary

vetch
variable noun: Vetch is a wild plant. Some types of vetch are sometimes grown as a crop.

vetch in American English
any of a number of leafy, climbing or trailing plants (esp. genus Vicia) of the pea family, grown chiefly for fodder and as a green manure
noun: any of several mostly climbing plants belonging to the genus Vicia, of the legume family, having pinnate leaves ending in tendrils and bearing pealike flowers, esp. V. sativa ( spring vetch), cultivated for forage and soil improvement

vetch in British English
noun: any of various climbing leguminous plants of the temperate genus Vicia, esp V. sativa, having pinnate leaves, typically blue or purple flowers, and tendrils on the stems