boring, dim, dumb, repetitive, dreary, stupid, tiresome, or tedious. Those are all opposites of dull.
sharp
dull
A dull story
Dull, unimaginative.
Dull or quiet
dull, inconspicuous, drab,
dull, boring, ordinary, plain tiresome, tedious, boring, dull, mind-numbing.
Anger, dull or upset.
colorless,colourles,dull
Dull, boring.
Comatose, sluggish, dull
bright intellligent sharp
Flat, dull, insignificant .