Triptych rhymes with:
cryptic, apocalyptic, cryptic, ecliptic, antiseptic, apocalyptic, coptic, cryptic, ecliptic, epileptic, fiberoptic, optic, peptic, septic, skeptic, synoptic
Triptych sounds like:
therapeutic, therapeutics, thereabouts, thrift's, thrifts, thrifts', torpedoes, torpedos, tribute's, tributes, tripods, truffaut's, turbotax