N.R.B is an abbreviation for what is known as a "No Reason Boner".A No Reason Boner is when a male randomly "gets hard" for no apparent reason.Also see boner.
by rundmc March 2, 2006

An Acronym for No Reason Boner
by CJ McMastaKewlio February 9, 2009

by Lorenzo October 12, 2004

by B.O.B. April 4, 2003

by joe mackdonald April 22, 2006

Zach; Did you see Evan got an N.R.B. in school today when he was akes to solve the problem on the board.
Ray; Yeah. How embarassing.
Ray; Yeah. How embarassing.
by John Dennis Riley February 6, 2008

by ImBeatenFrequently May 10, 2018
