To be fair, I believe they use those English words to describe them primarily because they are the same English words they use for Lights in the Abyssean chests.
The actual !! marker, when inspected in a DAT viewer like ModelViewer or Altanaviewer, is a gradient that transitions from Green to Yellow throughout the course of the actual model. It is green, it is yellow, and in the middle it is a mix of both. It is most definitely never literally Amber colored unless your monitor settings are totally wacky.
I don't care what people call it one way or another though. It's not too difficult to figure out what they mean. You could call it blurpleberry weakness for all I care.