Boss

I don't know, but there was this kid in my 6th grade class that always used "boss" to mean dick. He would brag about his boss and the K through 5th graders didn't understand and asked him why he had a job. Once you entered 6th grade, you learnt the true meaning of boss.

"What does fuck mean?" "Alright, Mrs. Turdmann is coming, so I can only tell you this once: A man's boss up a woman's butt."