Ponchan rhymes with:
abstention, circumvention, contravention, fanchon, inattention, intention, intervention, luncheon, muenchen, nonintervention
Ponchan sounds like:
pankonin, panmunjom, pengassan, penguin, pennsauken, pension, penson, phoenician, pi-meson, pinckney, pinkham, pinkney, pinshan, pinson, pinzon, pomicino, punkin