math ninja 

–noun, plural -ja, -jas. a member of a modern society of mathematical agents, highly trained in stealth calculatons and number theory, who are hired for covert purposes ranging from solving the worlds problems to passing on their skills to the next generation.

Mr. Harris is a math ninja.

math ninja by KSignell February 6, 2010

Ninja Math

Pioneered by Ken James (an engineering student at OSU), it is the ability to solve math and engineering problems without actually knowing how to do the problem. The technique involves ranking and ordering of numbers, canceling units, and other ninja like skills that enable you to at least approximate the correct answer, if not actually solve the problem.

Student: Damn! I can't do this.
Ken: It's answer "B"
Student: How do you know?
Ken: It's my mad ninja math skills. I can't explain how to do it because there is no real method, but if you know what to look for the answer just stands out.

Ninja Math by badpanda April 28, 2010