- the silky down that invests the seeds of a silk-cotton tree (kapoktree ),Ceiba pentandra, of the East Indies, Africa, and tropical America: used for stuffing pillows, life jackets, etc., and for acoustical insulation.
- a silky fibre obtained from the hairs covering the seeds of a tropical bombacaceous tree, Ceiba pentandra (kapok tree or silk-cotton tree): used for stuffing pillows, etc, and for sound insulation
