NSFN 

Not safe for neighbours means that you're listening to House Music and turn up the sub and bass to adequately buzzing levels. This of course is not safe for neighbours and will be sure to piss them off.

NSFN means you will get a knock on the door to turn that racket down, but at least you won't be able to hear the door!

Just listen to that bass, turn up to max volume NSFN!

NSFN by Benny XI August 18, 2020

NSFND 

Not Safe for North Dakota, who decided a fertilized egg has the same rights as a human. Thus an image of an egg being impregnated by sperm would be NSFND since it is, in their eyes, the same as a woman getting raped by many men.

Science: And here, in your health books, you can see that this little guy who has less brain cells than a fly, is impregnating the egg. Mind you, trillions upon trillions of these sperm are killed every time a man masturbates, and same goes for the unfertilized eggs, which are not living things. Hell you kill smarter things when you eat meat or step on bugs.
North Dakotan: HEY I CAN'T VIEW THIS! IT'S NSFND! AWW GEEZE, MIDGE!

NSFND by DougYoung March 2, 2009

NSFNH

Not Suitable For Noise Haters. Used to describe artistic content generally digestible by noise fans only.

NSFNH - s h r e d d e r - Endless generative noise track created with 256 bytes long MS-DOS program.

NSFNH by zden October 8, 2016

NSFND 

Not Safe For North Dakota
a picture that is pornography just in the state of North Dakota based of them giving human rights to fertilized eggs.

Created on www.reddit.com

A photo of my ultrasound is NSFND.

My unborn child is NSFND.

NSFND by Guest200990 March 2, 2009