The Collaborative International Dictionary of English v.0.48:

Ripple \Rip"ple\, v. i. [imp. & p. p. Rippled; p. pr. & vb. n.
   Rippling.] [Cf. Rimple, Rumple.]
   1. To become fretted or dimpled on the surface, as water when
      agitated or running over a rough bottom; to be covered
      with small waves or undulations, as a field of grain.
      [1913 Webster]

   2. To make a sound as of water running gently over a rough
      bottom, or the breaking of ripples on the shore.
      [1913 Webster]

WordNet (r) 3.0 (2006):

rippling
    n 1: a small wave on the surface of a liquid [syn: ripple,
         rippling, riffle, wavelet]