Manifold rhymes with:
billfold, blindfold, centerfold, eightfold, fivefold, ninefold, penfold, saffold, sevenfold, sixfold, tenfold, threefold
Manifold sounds like:
manipulate, manipulated, maplewood, mayfield, minefield, minnifield, mobility, mofield, muffled, muffoletto, mumbled