Short for "Gratuitous Picture Of Yourself," usually accompanied picture of yourself, or something that you do. Most commonly used on tumblr both in the main post and as a tag.
Person posts a gif of someone dancing like an idiot, "GPOY"
Person posts a picture of themselves making an awful face, "GPOY"
by Skanktasia March 16, 2011
GPOY is an initialism that literally stands for, "Gracious, Picture Of Yourself."

It is most often used to describe gifs, web comics, or pictures that apply so directly to your life it seems as if someone took a picture of you and put it up on the internet.

It is the equlivlent of saying, "Holy crap, I do this all the time! It's like the took a picture of me!"
*While looking at a .gif on Tumblr showing a reaction to someone reading over your shoulder*
Person: Hahahah, this is so me!
Comment: Lol GPOY!
by Tumbledore64 June 11, 2011
Giant Penis Over Yonder. When you see a picture and it's just amazing or has a great big hunk of penis in it.
*a picture of spiderman with an erection*
by LardDude32 May 14, 2011
God Pees On You.

It's another way of saying "Bad luck man!" or "You got Owned!" or "PWNED"
basicly, God hates you.
Person 1:"Ah shit man. That flying unicorn just nicked my spare pare of undies!"

Person 2:"PAHAHAHA!!! GPOY."
by Mong_Face February 7, 2011
gayest picture of you/yourself

When you post a really unattractive picture of yourself but it's too funny to not post.
by I'mnotreallyinnocent January 21, 2011
Gratuitous Picture Of Yourself, used a lot on tumblr; A picture of yourself, or something that you do like a gif of someone dancing like an idiot or a socially awkward penguin picture.
GPOY, too good to not post.
by HelenKeyes March 16, 2011