A measure of length, the twelfth part of a foot, commonly subdivided into halves, quarters, eights, sixteenths, etc., as among mechanics. It was also formerly divided into twelve parts, called lines, and originally into three parts, called barleycorns, its length supposed to have been determined from three grains of barley placed end to end lengthwise. It is also sometimes called a prime (´), composed of twelve seconds (´´), as in the duodecimal system of arithmetic. Note: The symbol ´ is the same symbol as the light accent, or the "minutes" of an arc. The "seconds" symbol should actually have the two strokes closer than in repeated "minutes", but in this dictionary ´´ will be interpreted as "seconds". "12 seconds (´´) make 1 inch or prime. 12 inches or primes (´) make 1 foot." Note: The meter, the accepted scientific standard of length, equals 39.37 inches; the inch is equal to 2.54 centimeters. See Metric system, and Meter.
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