unspeakable

Adjective

• too sacred to be uttered
  • the ineffable name of the Deity
    

• exceptionally bad or displeasing
  • atrocious taste
    
  • abominable workmanship
    
  • an awful voice
    
  • dreadful manners
    
  • a painful performance
    
  • terrible handwriting
    
  • an unspeakable odor came sweeping into the room
    

• defying expression or description
  • indefinable yearnings
    
  • indescribable beauty
    
  • ineffable ecstasy
    
  • inexpressible anguish
    
  • unspeakable happiness
    
  • unutterable contempt
    
  • a thing of untellable splendor
    

Related words

• Synonyms: 
  ineffable , unnameable , unutterable , atrocious , abominable , awful , dreadful , painful , terrible , indefinable , indescribable , untellable