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definitions

bros.

or Bros.

brothers.

bro

[broh, bruh]Slang.

noun, plural bros.

a brother.
a male friend or buddy.
a guy or fellow: used as a term of address.
a fellow black male; soul brother.
a young, usually white male variously and often negatively characterized as being preppy, party-loving, egotistical, sexist, etc.

adjective

of or relating to bros: the bro culture of college athletics.
Sometimes bruh [bruh] /brʌ/, brah [brah] /brɑ/.

Origin of bro

First recorded in 1830–40; reduced form of brother
Related formsbro·ish, adjective

bro.

or Bro.

plural bros. or Bros.

brother.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for bros.

bros.

Bros.

abbreviation for

brothers

bro.

abbreviation for

brother

bro

1

noun

NZ a family member
a close associate

bro

2

bra or bru

noun

Southern African informal a friend, often used in direct address

Word Origin for bro

C20: from Afrikaans broer brother
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for bros.

bro

n.

colloquial abbreviation of brother, attested from 1660s.

Online Etymology Dictionary, © 2010 Douglas Harper