bud (n.)

"undeveloped growth-point of a plant," late 14c., budde, origin unknown, perhaps from Old French boter "push forward, thrust," itself a Germanic word (compare Dutch bot "bud," Old Saxon budil "bag, purse," German Beutel), or perhaps from Old English budd "beetle."

"put forth or produce buds," c. 1400; see bud (n.). Related: Budded; budding.

familiar form of address for a male, 1851, perhaps a shortening of buddy (q.v.) and ultimately from brother.