1577: loophole Apr 9, 2019

Today, a 'loophole' means a lapse or inadequacy in something that can be used taken advantage of, and while it meant much the same thing in the 16th century, the initial subject matter was not rules, but walls. In the historical sense, a loophole was a hole through a wall from which someone could fire an arrow. In the late 16th century, the word 'loop' also denoted a an embrasure, so while those may have fallen out of style architecturally, the phraseology has persisted.
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