Definition from Wiktionary, the free dictionary
See also Buddy
- Colloquial butty (1802), meaning companion, also the form of an older dialect term meaning workmate, associated with coal mining. Itself believed derived from booty fellow (1530), a partner with whom one shares booty or loot. 
- Sometimes referred to in North American dictionaries as an alteration of brother.
buddy (plural buddies)
- A friend or casual acquaintance.
- They have been buddies since they were in school.
- A partner for a particular activity.
- drinking buddies
- An informal and friendly address to a stranger; a friendly placeholder name for a person one does not know.
- Hey, buddy, I think you dropped this.
- See also Wikisaurus:friend
friend or casual acquaintance
partner for a particular activity
informal address to a stranger