terrible - adjective

• causing fear or dread or terror
• exceptionally bad or displeasing
• intensely or extremely bad or unpleasant in degree or quality
• extreme in degree or extent or amount or impact

terrible - thesaurus

abominable   atrocious   awful   dire   direful   dread   dreaded   dreadful   fearful   fearsome   frightening   frightful   horrendous   horrific   painful   severe   tremendous   unspeakable   wicked