See humdrum in Webster's New World Roget's A-Z Thesaurus II
adjective
Arousing no interest or curiosity:
boring, drear, dreary, dry, dull, irksome, monotonous, stuffy, tedious, tiresome, uninteresting, weariful, wearisome, weary. See excite
noun
A tiresome lack of variety:
monotone, monotonousness, monotony, sameness. See change, excite
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