What’s the origin of “loophole”?

Dear Straight Dope: What is the origin of the term “loophole”? My Dad told me it was the name for those slits in castle walls through which archers would shoot their arrows, but I can’t see how that has anything to do with our current use of the term. Left wanting in Wayne, PA

Ken replies:

Strangely enough, your dad is correct. Most dictionaries make mention of the slit-like openings in castle walls that were used by archers (later, musketeers) to defend the castle. Our derivation of “loophole” as a way past a law is derived from this. The only openings in a seemingly impenetrable wall were these slits, which a child or small adult child could squeeze through. Thus, a loophole is a small opening, or “out,” in a seemingly airtight law, which only the clever few can use.

Ken

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What’s the origin of “loophole”?

A STAFF REPORT FROM THE STRAIGHT DOPE SCIENCE ADVISORY BOARD