The Collaborative International Dictionary of English v.0.48:

Grabble \Grab"ble\, v. i. [imp. & p. p. Grabbled; p. pr. & vb.
   n. Grabbling.] [Freq. of grab; cf. D. grabbelen.]
   1. To grope; to feel with the hands.
      [1913 Webster]

            He puts his hands into his pockets, and keeps a
            grabbling and fumbling.               --Selden.
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   2. To lie prostrate on the belly; to sprawl on the ground; to
      grovel. --Ainsworth.
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