Emphasis rhymes with:
metamorphasis, metamorphosis, analysis, antithesis, archdiocese, caucasus, dialysis, electrolysis, genesis, hydrolysis, hypothesis, metamorphasis, metamorphosis, morphogenesis, paralysis, pegasus, psoriasis, psychoanalysis, synthesis, thomasas
Emphasis sounds like:
embassies, embassy, embassy's, emboss, emphases, emphasize, emphasizes, envious, envisage, envisages, envos, envoys