The Collaborative International Dictionary of English v.0.48:

Whimper \Whim"per\, v. i. [imp. & p. p. Whimpered; p. pr. &
   vb. n. Whimpering.] [Cf. Scot. whimmer, G. wimmern.]
   To cry with a low, whining, broken voice; to whine; to
   complain; as, a child whimpers.
   [1913 Webster]

         Was there ever yet preacher but there were gainsayers
         that spurned, that winced, that whimpered against him?
                                                  --Latimer.
   [1913 Webster]

Moby Thesaurus II by Grady Ward, 1.0:

51 Moby Thesaurus words for "whimpering":
   Jeremianic, bawling, blubbering, complaining, cry, crying,
   dissolved in tears, faultfinding, fit of crying, flood of tears,
   fretful, good cry, greet, howling, in tears, lachryma, lachrymal,
   lachrymose, lachrymosity, lacrimatory, lamentive, melting mood,
   moanful, mournful, overflowing eyes, peevish, petulant, plaintive,
   plangent, puling, querulous, ready to cry, sniveling, sobbing,
   sorrowful, tear, tear bottle, teardrop, tearful, tearful eyes,
   tearfulness, tears, teary, ululant, wailful, weepiness, weeping,
   weepy, whining, whiny, with eyes suffused