Dinner

adjective, noun.

Dinner is homophones with the Chinese word/slang "低能", which means "of low energy/ability". It is further interpreted to describe someone/something that is boring, uncapable, or pointless.
This word is also an effective euphemism for various more offensive words.

- I heard that you guys read "The Dinner Party" for the final exam.
- Yeah... it's so short and dull.
- I'd say it's downright dinner.