noun arc·length \(ˌ)ärk-ˈleŋ(k)th, -ˈlen(t)th\

Definition of arclength




  1. :  the length of a segment of an arc Thus, in a unit circle (radius = 1), any angle of 1 radian cuts off an arc of unit length. All other arclengths are proportional to this; for instance, doubling the radius (to 2) and tripling the angle (to 3 radians) yields an arclength of 6. — Rheta N. Rubenstein et al., Math Horizons, November 2003

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Origin and Etymology of arclength

1arc + length

First Known Use: 1849

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capable of being understood in two ways

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