On Craigslist and other personnel sites, NSA stands for No Strings Attached or a romantic/sexual encounter without further obligation. If the "S" is replaced by a $ it means that payment is expected or, more simply, the person posting the ad is a prostitute.

See Nick at Nite

A variant of "n__n." The slashes represent blushing marks. Used to show that one is blushing, or embarassed. Asian based.

Nude for nude

Literally the fucking letter n

Why the fuck did you search this

Another way to say "No" for the lazy fucks who don't feel like typing the extra letter.

You have to agree that 'N' is a sad letter. Its the sad letter now. If you send or receive 'N' a sad has occurred