Here's what rhymes with indefinable.
definable undefinable Words that almost rhyme with indefinable
desirable viable sizable sizeable decidable liable undesirable excitable assignable likable likeable risible liveable deniable reliable advisable indescribable undeniable pliable inadvisable describable notifiable survivable unreliable indictable ascribable recyclable certifiable climbable unlikeable nonassignable unliveable identifiable justifiable unjustifiable verifiable libidinal realizable cognizable maniacal analyzable unverifiable rectifiable irreconcilable ammoniacal classifiable demoniacal reconcilable recognizable unidentifiable unrecognizable monomaniacal