evolvent

from The Collaborative International Dictionary of English v.0.48

Involute \In"vo*lute\, n. (Geom.)
   A curve traced by the end of a string wound upon another
   curve, or unwound from it; -- called also {evolvent}. See
   {Evolute}.
   [1913 Webster]

from The Collaborative International Dictionary of English v.0.48

Evolvent \E*volv"ent\, n. [L. evolvens, -entis, unrolling, p.
   pr. of evolvere.] (Geom.)
   The involute of a curve. See {Involute}, and {Evolute}.
   [1913 Webster]

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