the silky down that invests the seeds of a silk-cotton tree (ka·pok tree) Ceiba pentandra, of the East Indies, Africa, and tropical America: used for stuffing pillows, life jackets, etc., and for acoustical insulation.
any of several spiny trees belonging to the genus Ceiba, of the bombax family, having palmately compound leaves and seeds surrounded by silk cotton, especially C. pentandra, from which kapok is obtained.
