Cephalon rhymes with:
avalon, babylon, carillon, echelon, epsilon, avalon, babylon, carillon, echelon, epsilon, fenelon, guslan, halon, nylon, pylon, vanderlaan, waylon
Cephalon sounds like:
cableone, caplan, caplin, chaplain, chaplan, chaplin, choplin, cipollone, civilian, cofflin, copelan, copelin, coplan, coplen, coplin, coppolino, couvillion, couvillon