Pseudobombax pseu·do·bom·bax uncommon noun 1. tropical American deciduous shrubs or small trees Synonymsgenus Pseudobombax Related words Word family Pseudobombax ellipticum Broader terms dilleniid dicot genus Parts Bombacaceae Part of shaving-brush tree WordNet 2.1 (Princeton University). WordNet 2.1 Copyright Princeton University. All rights reserved.