Definition of "bro" []

• Slang A brother. (noun)
• Slang Friend; pal. Used as a form of familiar address for a man or boy: So long, bro. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "It meant you wore a backward hat, maybe waxed your chest, used the word "bro" a lot, drank Red Bull and vodkas, had a name for both your car and your penis, felt a reflexive need to high-five after sex, and would someday either work as a trader or just act like you did."
• "But we're getting back to a scene where Daren and his brother talk, and well, the bro is a bit uneducated."
• "The term bro was self-selected—because it’s a common form of address among bros—but is not universally used and is often employed pejoratively."