Orginally from the Scottish slang word "swagger" which was a description of the way some Scots walk (in a swaying motion), the word was then misinterpreted by the English as "the way someone presents themselves". Eg, whether someone looks cool.
The word quickly made its way to the states and has ever since become the catchphrase of douchbags and tools everywhere.
Person 1: "I think that guy off Jersey Shore has swag"
Person 2: "You're a dick"
Being so tired, you begin to show all the symptoms of being drunk, such as:
1) Stumbling and/or falling over
2) Confusion during conversation
3) Inabilty to type
4) The equivalent to drunk texting
5) Thinking this is funny when you submit it to Urbandictionary.
I'm drunktired. Help me up man, cause I want to see if I can buy a dolphin on ebay.