Estonians rhymes with:
washingtonians, amazonians, babylonians, caledonian's, jacksonians, jeffersonians, oregonians, smithsonian's, washingtonians, albanians, amazonians, argentinians, armenians, athenians, augustinians, babylonians, bosnian's, bosnians, bostonians, caledonian's, carolinians, chechnyan's, chechnyans, finian's, indianians, iranians, iranians', jacksonians, jeffersonians, jordanians, lithuanians, louisianians, oregonians, orleanians, palestinian's, palestinians, palestinians', panamanians, pennsylvanians, romanians, smithsonian's, stepanian's, ukrainian's, ukrainians, washingtonians
Estonians sounds like:
ecosystems, eighteen's, eighteens, ejecting, equating, equations, esteem's, exacting, exactions, exceeding, exciting, executing, executions, exhausting, existence, existing, exiting, extinguish, exuding