Imaginary numbers are not relevant at all. There’s nothing whatsoever to do with the everyday use of the word imaginary. They could just as easily have been called “vertical numbers” and real numbers called “horizontal numbers” in order to more clearly illustrate their geometric interpretation in the complex plane.

The term “imaginary number” was coined by Rene Descartes as a derogatory and the ill intent behind his term has stuck ever since. I suspect his purpose was theological rather than mathematical and we are all the worse for it.