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spherical triangle

American  

noun

Geometry.
  1. a triangle formed by arcs of great circles of a sphere.


spherical triangle British  

noun

  1. a closed geometric figure formed on the surface of a sphere that is bounded by arcs of three great circles

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of spherical triangle

First recorded in 1575–85