Boring

Dull, monotonous, repetitive, unrelieved, unvaried, unimaginative, uneventful; characterless, featureless, colorless, lifeless, insipid, uninteresting, unexciting, uninspiring, unstimulating; unreadable, unwatchable; jejune, flat, bland, dry, stale, tired, banal, lackluster, stodgy, vapid, monochrome, dreary, humdrum, mundane; mind-numbing, wearisome, tiring, tiresome, irksome, trying, frustrating; informal deadly, ho-hum, dullsville, dull as dishwater, plain-vanilla.