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
2. biology
having the margins rolled outwards
Word origin
C19: from Latin ēvolūtus unrolled, from ēvolvere to roll out, evolve
evolute in American English
(ˈɛvəˌlut)
noun
Geometry
a curve that is the locus of the center of curvature of another curve (called the involute); the envelope of the perpendiculars, or normals, of the involute