What’s the opposite?

I was reading the list of today’s official Days. One of them is Dewey Decimal Day.

In my sleepless haze I thought of decimal as the metric opposite of English or Imperial. Well, what’s the English version? LC. It’s based on a set of 21 letters, and then an irregular group of lettered subsets under each main letter. Nothing decimal or orthogonal about it. Long tons, short tons, hundredweights, stone, pounds, ounces, drams. Furlongs, leagues, miles, rods, chains, yards, feet, inches, barleycorns.