Source : Webster's Revised Unabridged Dictionary (1913)

Kapok \Ka*pok"\, n. [Prob. fr. the native name.] (Bot.)
   A silky wool derived from the seeds of {Ceiba pentandra}
   (syn. {Eriodendron anfractuosum}), a bombaceous tree of the
   East and West Indies.

Source : WordNet®

kapok
     n 1: from the kapok tree; used for stuffing and insulation [syn:
          {silk cotton}, {vegetable silk}]
     2: massive tropical tree with deep ridges on its massive trunk
        and bearing large pods of seeds covered with silky floss;
        source of the silky kapok fiber [syn: {ceiba tree}, {silk-cotton
        tree}, {white silk-cotton tree}, {Bombay ceiba}, {God tree},
         {Ceiba pentandra}]