Definitions of Kapok on the Web:

A short, lightweight, cotton-like, vegetable fiber found in the seed pods of the Bombocaceae tree. Because of its brittle quality, it is generally ...
www.lotusorganics.com/articles/ClothingGlossaryI-O.aspx

A Unicellular Seed Hair Obtained From The Fruit Pods Of The Kapok Tree Eriodendron Anfractuosum ( Formerly Known As Ceiba Pentranda)., Note. The Fibre Is Also Called Ceba, Ceiba, Java Cotton Silk Cotton, Silk Floss Etc. Indian Kapok Comes From Bombax Malabaricum.
www.fibre2fashion.com/glossary/glossary10.htm

the silky fibers around the seeds of any of several silk-cotton trees, esp. a ceiba (Ceiba pentandra): used for stuffing mattresses, life preservers, sleeping bags, etc.
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