A girlfriend just called me, looking for the answer to a trivia question that was asked in one of her meetings: Why is the airport code for O'Hare ORD?
Why she called me, I'm not sure, since she is as adept at googling as I. Nevertheless, a quick search on "ORD history" returned this lovely site. There appears to be some thought and logic put into the assigning of the codes, albeit rather convoluted and shortsighted thought and logic.
It's a wonder any planes get to the right place.
Naturally, you have to scroll all the way to the bottom of the article before you find the answer to the original question: The original airstrip was called Orchard Field.