Edouard Lemaitre edouard·le·maitre uncommon noun 1. Belgian cosmologist who proposed the big-bang theory of the origin of the universe (1894-1966) SynonymsLemaitreGeorges Henri LemaitreEdouard Lemaitre Related words Broader terms cosmologist WordNet 2.1 (Princeton University). WordNet 2.1 Copyright Princeton University. All rights reserved.