silk-cotton tree

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun Any of several trees having seeds surrounded by silky hairs, especially Bombax ceiba of tropical Asia.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A large tropical tree of the genus Bombax.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun 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