Who uses it: Castle architects and practitioners of siege warfare
What it means: Small windows in a castle or fortification wall that allow defending archers or snipers to shoot at attackers. They're also called "arrow loops" or "arrow slits."
How you can use it: Don't you already?
I'd never thought about the source of the modern term "loophole," until I saw the word used in a description of a siege. If you'd asked me, I'd have speculated that the term originated from knot-tying. It makes more sense that it means an opening in a fortification.
The one thing I meant to do yesterday (other than work) was get my car washed, and then I completely forgot. I believe that the Mr. Wash off Logan Circle opens very early, so I'll take the car over there this morning. It's hard to get one's car washed in Maine in the winter, just when it most needs washing.
After that, I'll pack up Dizzy and head to Annapolis, where we're picking up Chris Bea for the weekend. Then it's on to Maine, and I hope to get home before 10:00 tonight.