From Beyonce's "Irreplaceable",

1.) Dismissed, dumped, broke off

2.) "Step aside," as in when a person is dumped: means to get out of one's face and life so that a new partner can be established.

3.) Indicating where the door is located, even if it is not actually located to the left -- "To the left" indicates that your exit is expected right fucking now.

an expression Beyonce uses in her song "Irreplaceable" (written by NeYo) meaning homeboy can get his stuff, put it in a box, and leave. This signals the end of a relationship and that the man should pack everything he owns in a box and move to the left, out the door. Neyo described this expression to Tyra on the Tyra Banks show.

the universal order of passing a joint, a blunt or a bong when smoking weed

to describe when your more progressive (or liberal) than someone on the political spectrum

also used in the song "leavin'" by jesse mccartney. maybe he used it as a nod to beyonce

From Beyoncé's hit song irreplaceable

To the left is a reference to the fact that woman have no rights

A person/ or persons considered to be of unsound mind often resulting in being dissed/dismissed and rejected by a select peer group. Often used as a nickname bestowed on someone who has been rejected "to-the-left".