istg 

I Swear to God. Promising

She asked him out, istg!!!

istg by Dank Frank January 3, 2008

istg 

I swear to God~ it is a way of express you're being honest about something or expressing extreme annoyance at someone.

Friend~Your such a liar you dad didn't buy you a Lamborghini.
Me~He did, istg!

Friend~Ha Ha my parents are richer than you
Me~istg you so annoying ;-;

istg by XxZoexX July 27, 2020

Istg 

Istg is short for I swear to god

Istg, Hoseok is a ray of sunshine

Istg by Weird.flex.but.okay. February 18, 2019

istg 

I swear to god.

Jim : I ate your leftovers in the fridge 😛
Chloe: Istg if you did ill kill you!

istg by barbz 😍😛😋 February 1, 2021

istg 

I swear to God~ it is a way of express you're being honest about something or expressing extreme annoyance at someone.

Friend~Your such a liar you dad didn't buy you a Lamborghini.
Me~He did, istg!
(XxZoexX old acc)

istg by zoe ellys May 10, 2021

ISTG 

I swear to god

Istg someone just sent the most cutest paragraph ever

ISTG by Umaiya&Aman June 26, 2018

istg 

It's the acronym of "Is Sana the Gayest?" featuring Japanese member Sana of the Asia One Top Girl Group "TWICE" who is infamous of being "gay" with her members.

Istg? Of course!

istg by Lester Englandson May 19, 2019