NSFS 

"Not Safe For Straights", a tag mostly used on twitter by gay people, used during and before Pride Month, users are not allowed to post any straight content under their tweets, or the kpop stans will go after you.

It started as a mockery of "Not Safe For Ramadan", but is now widely used across twitter and is now yearly occurrences.

Yo not cool bro my name says right there (NSFS), why are you replying with men fucking pussies on my tweets?

NSFS by TheZetaSeries April 17, 2020

NSFS 

Not safe for school, like NSFW, but not safe for school instead of work.

Guys, check this site out... Careful though, its NSFS

NSFS by Anuj Saraswat June 9, 2005

NSFS 

Not Safe For Soul.

Dude two girls one cup is NSFS. Pain Olympics too. and 4Chan

NSFS by ZawesomeSaucem April 29, 2010

NSFS 

Not Safe For Starbucks

This picture is NSFS

NSFS by Yosef Solomon April 15, 2009

NSFS 

Naval Surface Fire Support: Fire provided by Navy surface gun and missile systems in support of a unit or units.

This is the USS Cole DDG-67 Arleigh Burke-class Aegis guided missile destroyer, requesting additional Naval Surface Fire Support.

NSFS by trampish July 7, 2005

NSFS 

when something is so shitty it isn't safe for sex

Yo that was some nsfs shit dude.

NSFS by Totally_Ryan September 16, 2017

NSFS 

Similar to NSFW, however stands for Not Safe For School, which is more strict than Not Safe For Work, including vulgar words, violent content, sexual content, etc.

This website is definitely NSFS
Just stay away from NSFS content

NSFS by Billiam Beaver May 21, 2017