Itching is actually derived from the Chinese word: I-Ching.
You may have heard of the children's rhyme as well: "I-ching/you ching/we all ching/for ICE Ching! This gradually evolved into Ice Cream of course, but in China there was no ice cream at the time (244 A.D.) so the children simply wished for more I Ching.
Now in case you don't know, and I know you don't, just fess up and you will feel much better about it, the I Ching is a book that details how to tell the future by throwing 'yarrow' sticks and then seeing what numbers come up. These numbers correspond to a page in the I Ching where you can find a sort of 'fortune cookie' prediction which you can then apply to your situation.
It's all very fascinating and I'm certain someone has written a Hub about it. If not, perhaps you might, if you can stop itching. Now you are making me itch! It's contagious.