from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A good friend; a comrade.
- n. A partner, especially one of a pair or team associated under the buddy system.
- n. Friend or comrade; chum. Used as a form of familiar address, especially for a man or boy: Watch it, buddy.
- intransitive v. To associate as a buddy or buddies: buddied around with the older guys.
- buddy up To ingratiate oneself, as by presuming friendship: buddied up to the coach in hopes of making the team.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A friend or casual acquaintance.
- n. A partner for a particular activity.
- n. An informal and friendly address to a stranger; a friendly placeholder name for a person one does not know.
- v. To assign a buddy, or partner.
Probably alteration of brother.(American Heritage® Dictionary of the English Language, Fourth Edition)