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French curve

or french curve

noun
  1. a flat drafting instrument, usually consisting of a sheet of clear plastic, the edges of which are cut into several scroll-like curves enabling a draftsperson to draw lines of varying curvature.

Origin of French curve

First recorded in 1880–85
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for french curve

French curve

noun
  1. a thin plastic sheet with profiles of several curves, used by draughtsmen for drawing curves
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