Truncheon rhymes with:
minchin, bastian, bostian, chechen, cochin, cutchin, derchin, duchin, kitchin, machin, minchin, patchin, paustian, pechin, qichen, turchin, turchyn, watchin'
Truncheon sounds like:
thronson, torrenzano, tranchina, transcon, transom