Western Samoa wes·tern·sa·moa uncommon noun 1. a constitutional monarchy on the western part of the islands of Samoa in the South Pacific SynonymsSamoaIndependent State of SamoaWestern SamoaSamoa i Sisifo Related words Word family Western Samoan monetary unit Broader terms country Parts Samoa Part of Apia WordNet 2.1 (Princeton University). WordNet 2.1 Copyright Princeton University. All rights reserved.