144 entries under plain topic. ×

66
boring(adjective, dreary, colorless, tedious, drab)
51
tedious(adjective, boring, uninteresting, dreary, monotonous)
47
flat(adjective, calm, quiet, set, hard)
42
uninteresting(adjective, boring, tedious, dreary, monotonous)
37
prosaic(adjective, set, weak, simple, tough)
36
monotonous(adjective, boring, uninteresting, uneventful, tedious)
35
drab(adjective, characteristic, hard, weak, simple)
31
dead(adjective, hard, weak, simple, flat)
30
humdrum(adjective, weak, simple, excite, slow)
29
lifeless(adjective, calm, weak, simple, tough)
26
insipid(adjective, hard, light, weak, kind)
24
bland(adjective, quiet, weak, kind, soft)
24
dry(adjective, calm, hard, simple, tough)
22
vapid(adjective, boring, uninteresting, flat, tedious)
20
commonplace(noun, adjective, set, hard, simple)
20
ordinary(adjective, common, boring, usual, commonplace)
17
unimaginative(adjective, simple, tough, flat, excite)
15
ho-hum(adjective, simple, flat, ordinary)
15
mundane(adjective, boring, simple, ordinary, tedious)
15
stale(adjective, set, hard, weak, simple)
<123458>
10 years ago|80k views|share |citing 
APASmart Define. (2016). dull thesaurus. Retrieved September 23, 2026, from https://smartdefine.org/dull/thesaurus/synonyms
ChicagoSmart Define. 2016. "dull thesaurus" https://smartdefine.org/dull/thesaurus/synonyms (accessed September 23, 2026).
HarvardSmart Define 2016, dull thesaurus, Smart Define, viewed 23 September, 2026, <https://smartdefine.org/dull/thesaurus/synonyms>.
MLASmart Define. "dull thesaurus" 29 March 2016. Web. 23 September 2026. <https://smartdefine.org/dull/thesaurus/synonyms>