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