Here's what rhymes with undecomposable.
disposable Words that almost rhyme with undecomposable
sociable unsociable negotiable nonnegotiable renegotiable potable notable controllable knowable unknowable consolable uncontrollable approachable unapproachable quotable erodible inapproachable notional inconsolable reproachable revokable emotional devotional irreproachable unemotional promotional overemotional