Origin: Old English wealhhnutu, from Wealh Welsh person, foreigner + hnutu nut; because it was brought into Britain from abroad
1 [countable] a slightly bitter nut with a large light brown shell: coffee and walnut cake2[countable] (also walnut tree) a tree that produces this type of nut3[uncountable] the wood from a walnut tree, often used to make furniture [Origin: Old English wealhhnutu, from Wealh Welsh person, foreigner + hnutu nut; because it was brought into Britain from abroad]