The Collaborative International Dictionary of English v.0.48:

Snow-capped \Snow"-capped`\, a.
   Having the top capped or covered with snow; as, snow-capped
   mountains.
   [1913 Webster]

WordNet (r) 3.0 (2006):

snow-capped
    adj 1: (of mountains) capped with a covering of snow

Moby Thesaurus II by Grady Ward, 1.0:

22 Moby Thesaurus words for "snowcapped":
   nival, niveous, snow-bearded, snow-blanketed, snow-capped,
   snow-clad, snow-crested, snow-drifted, snow-driven, snow-encircled,
   snow-feathered, snow-hung, snow-laden, snow-lined, snow-loaded,
   snow-mantled, snow-sprinkled, snow-still, snow-tipped, snow-topped,
   snowlike, snowy