Egretta albus eg·ret·taal·bus uncommon noun 1. the common American egret; a variety of the Old World white egret Casmerodius albus SynonymsAmerican egretgreat white heronEgretta albus Related words Broader terms egret Parts Egretta WordNet 2.1 (Princeton University). WordNet 2.1 Copyright Princeton University. All rights reserved.