n. & v.
n. 1 a any kind of leguminous plant with edible usu. kidney-shaped seeds in long pods. b one of these seeds. 2 a similar seed of coffee and other plants. 3 US sl. the head. 4 (in pl.; with neg.) US sl. anything at all (doesn't know beans about it).
v.tr. US sl. hit on the head. bean curd jelly or paste made from beans, used esp. in Asian cookery. bean sprout a sprout of a bean seed, esp. of the mung bean, used as food. full of beans colloq. lively; in high spirits. not a bean Brit. sl. no money. old bean Brit. sl. a friendly form of address, usu. to a man.
[ OE bean f. Gmc ]