sour grapes (noun)

1. After not getting the lead role in the film, he dismissed it as sour grapes and refused to watch it.

2. When his favorite character died in the series, he started criticizing it as sour grapes and claimed he never liked it anyway.

3. Unable to publish her own book, she began writing scathing reviews of bestselling novels, displaying sour grapes.

4. Feeling jealous of the popularity of another comic book artist, he resorted to sour grapes and belittled their work.