Pension rhymes with:
suspension, apprehension, ascension, attention, comprehension, condescension, contention, convention, detention, dimension, dissension, extension, gentian, henschen, hypertension, hypotension, invention, laurentian, mention, misapprehension, pretension, prevention, reinvention, retention, suspension, tension
Pension sounds like:
pankonin, panmunjom, pengassan, penguin, pennsauken, penson, phoenician, pi-meson, pinckney, pinkham, pinkney, pinshan, pinson, pinzon, pomicino, ponchan, punkin