Definition of evolute in English:


(also evolute curve)


  • A curve which is the locus of the centres of curvature of another curve (its involute).

    • ‘On 22 January 1769 Monge wrote to Bossut explaining that he was writing a work on the evolutes of curves of double curvature.’
    • ‘He defines evolutes and involutes of curves and, after giving some elementary properties, finds the evolutes of the cycloid and of the parabola.’
    • ‘Hence a curve has a unique evolute but infinitely many involutes.’
    • ‘He gives propositions determining the centre of curvature which lead immediately to the Cartesian equation of the evolute.’
    • ‘Of course the evolute of an involute of a circle is a circle.’


Zoology Botany
  • Rolled outwards at the edges.

    ‘an evolute shell’
    • ‘The general shell characters are the evolute coiling and the median keel that is always higher than the lateral ones.’
    • ‘The second lineage contained A. nitida, which became more involute and axially compressed on the umbilical side, and its first descendant, A. mckannai, which developed evolute coiling and a moderately wide umbilicus.’
    • ‘It essentially separates early (higher scores) and later (lower scores) representatives of the species, which tended to develop evolute coiling through geologic time.’
    • ‘Most clymeniids and contemporary goniatitids (with both evolute and involute shells) declined before the last anoxic episode, known as the Hangenberg event, which was followed by a major regression.’
    • ‘These younger descendants differ from Goniatites in their evolute inner whorls, their wider external lobe, and their higher median saddle.’


Mid 18th century from Latin evolutus, past participle of evolvere ‘roll out’ (see evolve).



/ˈiːvəl(j)uːt/ /ˈɛvəl(j)uːt/