UNIQUE WORDS game to increase our vocabulary - alphabetical order

Touchstone:  a hard black stone, such as jasper or basalt, formerly used to test the quality of gold or silver by comparing the streak left on the stone by one of these metals with that of a standard alloy.

an excellent quality or example that is used to test the excellence or genuineness of others.

 Moonlight:

This has not to do with the game 

I just noticed it started with 'K' instead of 'R', my bad..got too excited to join the game, missed the alphabetical order condition.

That said, I don't think it has nothing to do with the game. It's an actual term with clear meaning and context provided. Plus it's a unique one you can't find it in dictionary.