The natural progression of language by means of:
1.) Abbreviation (bro from brother)
2.) Word reversal (cool and hot for good)
3.) A need for secrecy (dime bag for $10 of pot or
1/10oz of
weed)
4.) Degree of separation (green for
marijuana)
5.) Expressed honorific (calling a close friend your brother)
6.) Combination (Branjalina for Brad Pit and Angelina Jolie)
7.) Any other word not recognized by the major dictionaries as viable, but which a large portion of the population will understand the meaning of.
Though he did not
allow slang to be used in his classroom, Prof. Smith was known to call his students "
dude", "man", and "bro"
outside of class in a feeble attempt to regain some of his lost youth.