a. Geom. [f. COL- together + LINEAR, f. L. līnea line.] Lying in the same straight line.

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1863.  R. Townsend, Mod. Geom., I. 168. A system of points ranged along a line is termed a collinear system.

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1882.  Minchin, Unipl. Kinemat., 214. Two points, A′, B′, which are collinear with C.

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  † b.  Lying in the same plane. Obs.

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1726.  Leoni, Alberti’s Archit., III. 6 a. Superficies are said to be … Col-linear, when a continued strait line will touch them equally every where. Ibid., III. 7 a. Some are col-linear with the Visual Rays.

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