ISN 

ISN stands for I send nudes

Me: Hey guess what
Person: what
Me: ISN
Person: Fuck yes

ISN by Lightningbolt1999 September 5, 2019

isn 

uber1337 person

ISN 0wnz y0 all

isn by ISN June 5, 2003

Isn 

Maybe or might be may or may not

Someone isn feeling a lil blue today, said the doctor

Isn by Fratelo January 3, 2021

isn't defined yet 

A message that appears when you search UrbanDictionary for something that is non-existent/undefined. Occasionally after reading this message follows a sense of disappointment.

"Isn't defined yet" isn't defined yet. I guess I'll write up a definition.

isn't defined yet by _pryat January 29, 2009

Isn't It Iron Pick

Isn't It Iron Pick, is likely referring to the minecraft advancement.

The advancement itself is a reference to the well-known pop song "Ironic" by Alanis Morissette.
The lyrics are as follows; "And isn't it ironic? Don't you think".

The advancement in and of itself is also a pun on the word "ironic".

"Isn't It Iron Pick: Upgrade your pickaxe"

Isn't It Iron Pick by Psypixel March 6, 2022

Isn'trael

Da fake country where scammers are calling from.

Many scammers can't even spell correctly, so even if they claim to be calling from "Isreal" (which, of course, definitely IS NOT a "real" country; you should already know da correct spelling of said Middle Eastern country --- I-s-r-A-E-l --- from having learned it in grade school), you would be wise to suspect dat they are actually located in ISN'TRAEL!

Isn'trael by QuacksO February 3, 2021

isn’t it just 

Used to strongly agree with what someone has said about something or someone.

Heather - This is so expensive!
Veronica - Isn’t it just!

isn’t it just by Chinky Chonky April 28, 2019