17
stereotyped(adjective, dull, set, hard, flat)
17
vapid(adjective, dull, set, weak, simple)
15
dead(adjective, dull, quiet, hard, weak)
15
rotten(adjective, strong, offensive, sweet, rank)
15
uninteresting(adjective, dull, weak, flat, warm)
14
threadbare(adjective, dull, set, beat, hard)
13
antiquated(adjective, hard, last, original, tired)
13
mouldy
13
unoriginal(adjective, dull, set, hard, flat)
12
common(adjective, dull, set, hard, simple)
12
humdrum(adjective, dull, simple, flat, clean)
12
rancid(adjective, rank, corrupt, foul, disgusting)
12
spoiled(adjective, hard, corrupt, disgusting, old)
12
tiresome(adjective, dull, flat, stupid, ordinary)
11
fetid(adjective, strong, hard, warm, offensive)
11
putrid(adjective, quiet, strong, offensive, sweet)
11
rank(adjective, hard, corrupt, foul, disgusting)
11
sour(adjective, hard, rank, corrupt, foul)
10
jejune(adjective, dull, set, weak, flat)
10
moth-eaten(adjective, dull, set, hard, flat)
11 years ago|26k views|share |citing 
APASmart Define. (2015). stale thesaurus. Retrieved September 22, 2026, from https://smartdefine.org/stale/thesaurus/synonyms
ChicagoSmart Define. 2015. "stale thesaurus" https://smartdefine.org/stale/thesaurus/synonyms (accessed September 22, 2026).
HarvardSmart Define 2015, stale thesaurus, Smart Define, viewed 22 September, 2026, <https://smartdefine.org/stale/thesaurus/synonyms>.
MLASmart Define. "stale thesaurus" 10 April 2015. Web. 22 September 2026. <https://smartdefine.org/stale/thesaurus/synonyms>