dull

abate arid barren benumbed blank bland blear bleary bloodless blunter blunt boring bored bromidic chalky cheerless cloudy colorless colorless corny dampen dark darker darkest deaden dense denser depress depresses diffuse dim dim dim dimmer dimmer dingy dim-witted dismal dowdy downcast drawling dragging dreary dumb dumbest dumber dusky dysphoric earthy everyday expressionless fade faded fainter faint fatuous feeble-minded frumpish frumpy fusty garden-variety gloomy gloomy glassy gravest grave half-witted harden hazy heavy-hearted heavy heavy hebetudinous heaviest heaviest hokey ho-hum hollow humdrum idiotic imbecile inactive inanimate inapt inert inexpressive inkhorn insentient institutional interminable iterative jejune lackadaisical lagging languishing lazier lazy leaden leaden lethargic listless lumpish matter-of-fact mediocre melancholic menial mid mild mitigate monotonous more boring most inactive most vacuous mousy muddy muffle muffled murky musty nondescript numb obtuse opaque ordinary overcast overused pale pale pales pallid pasty pedantical pedantic phlegmatic plain platitudinal platitudinous pokerfaced ponderous ponderous prolonged prosaic purblind quieten quietened quell quelled ready-made reiterative relieve relieves repetitious repetitive roily roiled rustic sallow shush silence simple-minded simple simpler slack slack slavish slothful slower slower slow slow slowest slowest slow-witted smoggy soft softer somber somnifacient soporific spiritless stale stereotyped stereotypical stolid stock stocker stuffy stultify stupid stupefies stupefies stuporous stupefy stupefy sullen supine tarnish tasteless tarnishes tepid thick thick thick-witted thickheaded threadbare thoughtless tiresome torpid trite tristful turn unappealing uncomprehending undistinguished unexceptional uninteresting unmotivated unperceptive unprogressive unsavory unsightly vacuous warmed-over washed-out waterish weak weariful weaker weakest wearisome wearisome whiten