It's an acronym, that is, a word formed from the first letters of an expression in English. In this case would be: quot; bae quot; = before anyone else, that in English means before anyone or before any.There is another version that says it's an abbreviation in English of the word quot; quot; babe that means baby.Another example of acronym very frequent in networks social is: omg or OMG = Oh my God, whose meaning is Oh God mine!