Opiate rhymes with:
amiot, appropriate, associate, baccalaureate, chariot, cheviot, compatriot, cypriot, eliot, elliot, elliott, garriott, grilliot, harriet, harriott, idiot, immediate, iscariot, jacksdeit, jeanniot, lariat, laureate, marriott, merriott, parriott, patriot, proletariat, radiate, remediate, roseate, secretariat, soviet
Opiate sounds like:
obadiah, obeid, obeyed, obit, obviate, obviated, offbeat, offutt, oft, opt, opted, opto, ovate, ovett, oviatt, oviedo, ovitt, ovoid