Nobody complains that r, o, y, g, b, i, and v aren't actual colors, do they? Other than you, I mean.
http://en.wikipedia.org/wiki/List_of_mnemonics
What does K equal in hexadecimal? Well, it isn't defined for hexadecimal. K=20 is only defined in Base 21 and above.
Other than me? Hah, nice cheap shot, pole ;-)
Edit: The 0x communicates that the mnemonic is illustrating base 16, so your objection below is not valid.
Nobody complains that r, o, y, g, b, i, and v aren't actual colors, do they? Other than you, I mean.
http://en.wikipedia.org/wiki/List_of_mnemonics