Nilsson nils·son US/ˈnɪlsʌn/ uncommon noun 1. Swedish operatic soprano who played Wagnerian roles (born in 1918) SynonymsBrigit NilssonMarta Brigit Nilsson Related words Broader terms soprano WordNet 2.1 (Princeton University). CMU Pronouncing Dictionary. WordNet 2.1 Copyright Princeton University. All rights reserved.