1 adj If you say that someone or something is hideous, you mean that they are very ugly or unattractive.
(=monstrous, horrible)
She saw a hideous face at the window and screamed.
2 adj You can describe an event, experience, or action as hideous when you mean that it is very unpleasant, painful, or difficult to bear.
(=horrendous)
His family was subjected to a hideous attack by the gang...