To be scunnered means to be fed up or disgusted with something.
It's a feeling of being really tired of something or not liking it at all.
Examples:
I'm scunnered with all this rain.
She's scunnered with doing the same thing every day.
He's scunnered with his job.
I'm so scunnered with this broken toy!
I'm scunnered with waiting for so long.
She's scunnered with eating the same food every day.