It's a medieval measurement, still in popular use. Nowadays it means approximately 2.54 centimeters. Historically, it's the height of the ash pile a "witch" would leave behind, and the word has morphed only slightly from "witches" into "inches."
Actually nowadays it means exactly 2.54 cm as that’s how it is defined. Which also means all distance measured in US Customary units is ultimately metric too
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It's a medieval measurement, still in popular use. Nowadays it means approximately 2.54 centimeters. Historically, it's the height of the ash pile a "witch" would leave behind, and the word has morphed only slightly from "witches" into "inches."
Actually nowadays it means exactly 2.54 cm as that’s how it is defined. Which also means all distance measured in US Customary units is ultimately metric too