The Collaborative International Dictionary of English v.0.48:

Dwindle \Dwin"dle\, v. i. [imp. & p. p. Dwindled; p. pr. & vb.
   n. Dwindling.] [From OE. dwinen to languish, waste away,
   AS. dw[imac]nan; akin to LG. dwinen, D. dwijnen to vanish,
   Icel. dv[imac]na to cease, dwindle, Sw. tvina; of uncertain
   origin. The suffix -le, preceded by d excrescent after n, is
   added to the root with a diminutive force.]
   To diminish; to become less; to shrink; to waste or consume
   away; to become degenerate; to fall away.
   [1913 Webster]

         Weary sennights nine times nine
         Shall he dwindle, peak and pine.         --Shak.
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         Religious societies, though begun with excellent
         intentions,
         are said to have dwindled into factious clubs. --Swift.
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