Nigeria's rhymes with:
bacteria's, cafeterias, confiterias, iberia's, liberia's, syria's, algeria's, andrea's, area's, areas, arias, austria's, bacteria's, bavaria's, bulgaria's, cafeterias, confiterias, deandrea's, farias, iberia's, koreas, liberia's, peoria's, peria's, pretoria's, rosaria's, syria's, victoria's, victorias
Nigeria's sounds like:
nagorski, naysayers, nazer's, necrosis, negroes, negros, neikirk, new-jersey, new-jersey's, newkirk, newswires, niagara's, nicaragua, nicaragua's, nigger's, niggers, nigris, nongreek, nosair's, nucor's