Green’s Dictionary of Slang

n.b.d. phr.

[abbr. no big deal]

(US campus) a general expression of nonchalance.

1981
199020002010
2014
Show quotations
[US]Eble Campus Sl. Mar. 5: NBD – [...] ‘How was the frat party?’ ‘NBD.’.
[US]Eble Sl. and Sociability 37: Two kinds of shortening reduce words to letters. The dominant type in college slang is initialism, which names the individual letters: [...] NBD (no big deal).
[US]C. Eble (ed.) UNC-CH Campus Sl. Spring 2014.