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English definition of “diameter”

diameter

noun [C/U]    /dɑɪˈæm·ɪ·t̬ər/
geometry the distance from one side to the opposite side of a circle, measured by a line passing through the center of the circle: [C] We need a pipe with a diameter of about six inches.
(Definition of diameter noun from the Cambridge Academic Content Dictionary © Cambridge University Press)
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