The Collaborative International Dictionary of English v.0.48:

Sinuosity \Sin`u*os"i*ty\, n.; pl. Sinuosities. [Cf. F.
   sinuosit['e].]
   1. Quality or state of being sinuous.
      [1913 Webster]

   2. A bend, or a series of bends and turns; a winding, or a
      series of windings; a wave line; a curve.
      [1913 Webster]

            A line of coast certainly amounting, with its
            sinuosities, to more than 700 miles.  --Sydney
                                                  Smith.
      [1913 Webster]