evolute

American  

[ev-uh-loot, ee-vuh-] / ˈɛv əˌlut, ˈi və- /

noun

Geometry.

1. the locus of the centers of curvature of, or the envelope of the normals to, another curve.

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evolute British  

/ ˈɛvəˌluːt /

noun

1. 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

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adjective

1. biology having the margins rolled outwards

Etymology

Origin of evolute

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

Example Sentences

Both of these liquids have specific pericosities given by P = 2.5C.n^6-7 where n is the diathetical evolute of retrograde temperature phase disposition and C is Cholmondeley's annular grillage coefficient.

From Time Magazine Archive

Of more interest is the balustrade at Number 207 La Grange Alley with its evolute spiral band and slender ball spindles beneath.

From The Colonial Architecture of Philadelphia by Cousins, Frank

The pleasing effect of the design at Seventh and Locust streets is largely due to appropriate use of the evolute spiral band.

From The Colonial Architecture of Philadelphia by Cousins, Frank

The evolute of this ellipse is the caustic required.

From Encyclopaedia Britannica, 11th Edition, Volume 5, Slice 5 "Cat" to "Celt" by Various

It matters little whether a person can correctly derive the words telegraph, tangent, ellipse, evolute, etc., if the correct idea is present in his mind when he uses them.

From Popular scientific lectures by Mach, Ernst