Imaginary-number Synonyms

A type of complex number in which the multiple of i (the square root of −1) is not equal to zero. Examples of imaginary numbers include 4 i and 2 − 3 i , but not 3 + 0 i (which is just 3).
  1. pure imaginary {compare complex number
  2. real-number
(mathematics) a number of the form a+bi where a and b are real numbers and i is the square root of -1