Synonyms for Monotonous:

adj.

all (adjective)
humdrum.
all the same, remaining the same (adjective)
prosaic, repetitive, boring, tiresome, monotone, unchanging, dreary, recurrent, uniform, tedious, humdrum, flat, unvarying, wearisome, unchanged, wearying, uninteresting, dull.
boring (adjective)
humdrum, wearisome, depressing, prosaic, Weariful, insipid, uninteresting, tiresome, dreary, mundane, dull, commonplace, dry, boring, tedious.
continuous (adjective)
lasting, robot-like, regular, steady, ceaseless, persistent, repeated, continual, unchangeable, consistent, invariable, undying, unremitting, monolithic, un-intermittent, flat, cyclical, straight, homogeneous, unchanging, sequential, habitual, featureless, unbroken, perpetual, endless, consecutive, indefatigable, incessant, constant, connected, repetitive, interminable, perennial, unending, level, unvarying, even, uniform, unceasing, nonstop, gapless, undeviating, continuing, continuous, seamless, coherent, recurrent, everlasting.
frequent (adjective)
frequent, recurrent.
insensitive (adjective)
dull.
regular (adjective)
everyday, accustomed, orthodox, commonplace, cyclical, normal, epochal, customary, canonical, frequent, habitual, universal, rhythmic, traditional, stock, mundane, continual, Predominating, chronic, conventional, metronomic, periodic, steady, standard, prevailing, common, usual, regular, constant, ordinary, Familiar, routine, average, recurrent, general.
smooth (adjective)
undeviating.
unimaginative (adjective)
prosaic.

n.

adenoidal, breathy, appealing, disembodied, croaky, grating, brittle, fruity, dead. ceremonial, single, antisocial, collaborative, varying, clerical, multiple, cooperative, assistant, various, casual, unchanged, associate, adjunct, collegiate. drear, Irksome, stuffy, Weariful, weary, excite. monotonous (noun)
dull, unmusical, humdrum, unmelodic, unmelodious, monotone, monotonic.
tiresome (noun)
wearying.

Other synonyms:

drear, Weariful. Irksome. stuffy, weary. brittle. Other relevant words:
cooperative, croaky, fruity, clerical, adenoidal, excite, stuffy, unchanged, multiple, collaborative, disembodied, appealing, monotone, Weariful, grating, breathy, wearying, various, Irksome, weary, assistant, antisocial, dead, unmelodic, unmusical, monotonic, varying, casual, collegiate, unmelodious, single, adjunct, associate, drear, ceremonial, brittle.

Usage examples for monotonous

  1. And now, leaning against the rail in front of her, he found the sunset duller, more monotonous and commonplace than the human combination in the steamer- chair. – The Pines of Lory by John Ames Mitchell
  2. For a week he did no more than speak to me a word when business made it needful, and then the monotonous days went on as before in the gray, dismal home, out of which the light of life's gladness departed when those dear mother- eyes were closed in death. – Hugh Wynne, Free Quaker by S. Weir Mitchell
  3. There is no drama so low- voiced and serene and monotonous – Last Words by Stephen Crane