circular mil

American  

noun

1. a unit used principally for measuring the cross-sectional area of wires, being the area of a circle having a diameter of one mil.

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circular mil British  

noun

1. a unit of area of cross section of wire, equal to the area of a circle whose diameter is one thousandth of an inch. 1 circular mil is equal to 0.785 × 10 ^–6 square inch or 0.2 × 10 ^–9 square metre

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