Optus rhymes with:
eucalyptus, actus, aeltus, alatas, albertus, altus, anacortes, apparatus, apprentice, armistice, arthritis, artus, asbestos, augustus, bartus, batus, berettas, bronchitis, brountas, brutus, cactus, calamitous, cetus, circuitous, coitus, comitatus, copetas, countess, curtis, decurtis, denktas, detritus, dittus, divinitas, duplicitous, emeritus, encephalitis, equitas, erastus, eucalyptus, eustace, eustis, faustus, felicitous, feltus, festus, fetus, fleitas, fortas, fortuitous, fremitus, gastritis, gittis, glottis, gratis, gratuitous, gravitas, gustus, hepatitis, hiatus, hippolytus, homo-erectus, hostess, impetus, justice, justus, koskotas, laryngitis, lattice, lettuce, lintas, loftus, lotus, lotus', malpractice, margaritas, martus, mastoiditis, meningitis, milpitas, momentous, mottus, notice, osteoarthritis, pettus, pilatus, pocahontas, portentous, poultice, practice, precipitous, priestess, prophetess, prospectus, proventus, qantas, rastus, riotous, robustas, santas, serendipitous, sextus, situs, solicitous, status, stratus, thetis, titus, tortoise, treatise, ubiquitous, unitas, wojtas, zemaitis
Optus sounds like:
obits, obtuse, obviates, opdyke, opiates, opitz, optek, optic, optica, optics, opts, ovett's, oviatt's, ovitt's, ovitz, ovitz's