Out of curiosity I googled to see if there's formal names to things beyond UV and a SO question came up saying Klingon has a word for a color that falls within the UV spectrum, Amarklor; it "falls between violet amarklor (dark violet or purple) and amaklor-kalish (almost black)".

Else there's Octarine from the Discworld books, it's the colour of magic.

Another one in that same SO thread is err, quantifying synesthesia in the study of "chromophonics", where sound is assigned a color and vice-versa, that is, one could name a colour after a sound, which matches up with the earlier "octave" analogy.

> "blue above visible blue"

Good name for a rock band. Or some tv series.