A pair of values 
and 
one or both of which is complex.
Imaginary Point
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References
Woods, F. S. Higher Geometry: An Introduction to Advanced Methods in Analytic Geometry. New York: Dover, p. 2, 1961.Referenced on Wolfram|Alpha
Imaginary PointCite this as:
Weisstein, Eric W. "Imaginary Point." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/ImaginaryPoint.html