evolute

[ev-uh-loot or, esp. British, ee-vuh-]

noun Geometry.

the locus of the centers of curvature of, or the envelope of the normals to, another curve.Compare involute(def 5).

Origin of evolute

1720–30; < Latin ēvolūtus (past participle of ēvolvere to roll out, unfold, evolve)

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for evolute

Historical Examples of evolute

By and by that flour-sack is going to evolute into an underskirt for me to wear under my dress when I go to school.
The Story of Opal
Opal Whiteley
This point evidently lies upon the branch zM of the evolute in Fig. 23.
Scientific American Supplement, No. 595, May 28, 1887
Various
The evolute of a curve is the curve which is the envelope of all its normals or the locus of all its centres of curvature.
The New Gresham Encyclopedia
Various
These names are given to the curves because the end of a stretched thread unwound from the evolute will describe the involute.
The New Gresham Encyclopedia
Various
A curve which has a given curve as evolute is called an “involute” of the given curve.
Encyclopaedia Britannica, 11th Edition, Volume 14, Slice 5
Various

British Dictionary definitions for evolute

evolute

noun

a geometric curve that describes the locus of the centres of curvature of another curve (the involute). The tangents to the evolute are at right angles to the involute

adjective

biology having the margins rolled outwards

Word Origin for evolute

C19: from Latin ēvolūtus unrolled, from ēvolvere to roll out, evolve

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