IPA: /ˈdʌlɪst/
KK: /dʌlɪst/
The least interesting or exciting; lacking brightness or sharpness.
The movie was the dullest I've ever seen, and I almost fell asleep.
Comparative: duller
Superlative: dullest
Dullest → It is formed from "dull" (from Old Norse "dullr", meaning blunt or not sharp) and the suffix "-est" (used to form the superlative degree). The word "dullest" means the most blunt or lacking in sharpness or interest.
Think of something that is the "most blunt" or lacking in excitement — that's what "dullest" means.
No commonly confused words.