adjective

errible is a word to say something is very bad. There are a couple different ways it can be bad:

Really unpleasant or scary: This is the original meaning of terrible.
Very bad quality: This is how we use it most often now. Like a terrible movie or a terrible haircut.
Making you feel unwell: You can also use terrible to describe how you feel when you're sick or sad.

Example

1. My toast burned, so now I have terrible breakfast.
2. The movie had terrible jokes, so we left early.
3. I feel terrible because I forgot my friend's birthday.