buddy

[ buhd-ee ]
/ ˈbʌd i /
Informal.

noun, plural bud·dies.

comrade or chum (often used as a term of address).
bud2.

verb (used without object), bud·died, bud·dy·ing.

to be a companion; be friendly or on intimate terms.

Verb Phrases

buddy up,
  1. to become friendly; be on friendly or intimate terms.
  2. to work closely together: to buddy up with a student from another high school.
buddy up to, to become friendly with or curry the favor of: He was buddying up to the political bosses.

Origin of buddy

1840–50, Americanism; perhaps reduced form of brother

British Dictionary definitions for buddy up

buddy
/ (ˈbʌdɪ) /

noun plural -dies

mainly US and Canadian an informal word for friend Also called (as a term of address): bud
a volunteer who visits and gives help and support to a person suffering from AIDS
a volunteer who gives help and support to a person who has become disabled but is returning to work

verb -dying or -died

(intr) to act as a buddy to a person suffering from AIDS

Word Origin for buddy

C19: probably a baby-talk variant (US) of brother

Idioms and Phrases with buddy up

buddy up

Be very friendly, as in He is always wanting to buddy up with me, but I don't really like him. [Slang; early 1900s]