look up any word, like half chub:
 
1.
A portmanteau of "j" and "imaginary" for the imaginary component of a complex number. This means the same thing as Imaginary Number, and typically this number would have an italicized i after it. In electrical engineering, the letter "i" has other and more apparent meanings, so to avoid confusion we pick the next letter, j.
Compare imaginary with jimaginary number
Sheldon would use 1 + 2i.
Howard would use 1 + 2j.
by brokenbrain October 25, 2011
 
2.
The square root of -1 in electrical engineering.
The impedance of this wire is 7 ohms plus the jimaginary number.
by Senator Penguin June 20, 2007