Meaning of involute in English:


Pronunciation /ˈɪnvəl(j)uːt/


  • 1 formal Involved or intricate.

    • ‘the art novel has grown increasingly involute’
    complex, complicated, convoluted, tangled, entangled, ravelled, twisted, knotty, maze-like, labyrinthine, winding, serpentine, circuitous, sinuous
  • 2 technical Curled spirally.

    1. 2.1Zoology (of a shell) having the whorls wound closely round the axis.
      ‘Most contemporary goniatitids had an involute shell with compressed whorls.’
      • ‘In the Anaspidea there is a tendency for parapodia to enlarge and, together with the mantle, to enclose the fragile shell (with increasingly reduced and involute spire).’
      • ‘Although no equatorial sections were recovered, the present specimens exhibit a likely involute initial stage followed by biserial, uncoiled later stage in which chambers are more flattened.’
      • ‘The fundamental structure of the proloculus is the innermost part of the spirally arranged shell; it resembles the involute type of planispirally arranged foraminifera tests.’
      • ‘They evolved in the Devonian, comprising evolute to involute planispirally coiled conchs quite similar to that of the contemporaneous nautiloids.’
    2. 2.2Botany (of a leaf or the cap of a fungus) rolled inwards at the edges.
      ‘They were found to comprise at least three different traits: involute leaves, early flowering, and Apetala flowers.’
      • ‘Distinguishing characteristics are fully double, involute florets that are narrow and pointed.’
      • ‘This mutant displayed involute leaves and early flowering, although less than clf and icu2 mutants (20 days after sowing).’


  • The locus of a point considered as the end of a taut string being unwound from a given curve in the plane of that curve.

    Compare with evolute

    ‘Since normals to a straight line never intersect and tangents coincide with the curve, evolutes, involutes and pedal curves are not too interesting.’
    • ‘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.’
    • ‘The evolute and the involute of an equiangular spiral is an identical equiangular spiral.’
    • ‘Both the evolute and involute of a cycloid is an identical cycloid.’


Mid 17th century from Latin involutus, past participle of involvere (see involve).