Here's what rhymes with unofficinal.
                        
                        
                    
                                medicinal  Words that almost rhyme with unofficinal
additional  positional  provisional  divisional  oppositional  volitional  traditional  conditional  nutritional  transitional  unconditional  compositional  depositional  cognitional  inquisitional  prepositional  propositional  definitional  dispositional  nontraditional  original  fictional  syllable  miscible  fixable  finagle  kissable  criminal  typical  visible  visual  digital  miracle  permissible  admissible  occipital  pitiful  frictional  pinnacle  polygonal  thinkable  binnacle  spiracle  tillable  unoriginal  billable  nonfictional  steerable  biddable  winnable  mixable  sinkable  individual  political  principle  clinical  principal  municipal  biblical  mythical  aboriginal  episcopal  invincible  pivotal  satirical  unthinkable  inadmissible  livable  antipodal  pinochle  thimbleful  unsinkable  resistible  refillable  shrinkable  bridgeable  invisible  reciprocal  irresistible  hospitable  inexplicable  juridical  despicable  divisible  derivable  transmissible  quizzical  drinkable  printable  undrinkable  unprintable  unlivable  utilisable  ignitible  nonrefillable  equivocal  unequivocal  explicable  jurisdictional  biophysical  geophysical  pontifical  subclinical  diacritical  nonclinical  forgivable  nonreciprocal  transmittable  extricable  relivable  predictable  unpredictable  transcriptional  psychophysical  archiepiscopal  unforgivable  astrophysical