(n.) The act of deriving equations just for the sake of deriving them, at no apparent gain to the student.
In verb form, to mathturbate is to perform such menial mathematical labor.
mathturbatory: characterized by excessive mathturbation
"The professor spent three hours deriving the equation on the board because he thought it would help us understand the concept better; really, however, he just confused us with his senseless mathturbation."
"The homework problem required hours of mathturbation, with the end result being a simple identity that appears in the index of every text."
The art of discussing ideas in way so as to spend maximum time, while achieving minimal result. It is also used when people try and use intelligent sounding words to conceal their low knowledge levels about an unknown subject.
Mathurbation - My boss mathurbated with me for an hour today I need a cigarette after 2 hours of mathurbation