#1 dull a. lacking in liveliness or animation; "he was so dull at parties"; "a dull political campaign"; "a large dull impassive man"; "dull days with nothing to do"; "how dull and dreary the world is"; "fell back into one of her dull moods". wn
#2 dull a. emitting or reflecting very little light; "a dull glow"; "dull silver badly in need of a polish"; "a dull sky". wn
#3 dull s. [boring, deadening, ho-hum, irksome, slow, tedious, tiresome, wearisome] so lacking in interest as to cause mental weariness; "a boring evening with uninteresting people"; "the deadening effect of some routine tasks"; "a dull play"; "his competent but dull performance"; "a ho-hum speaker who couldn't capture their attention";. wn
#4 dull s. (of color) very low in saturation; highly diluted; "dull greens and blues". wn
#5 dull v. make dull in appearance; "Age had dulled the surface". wn
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