19
long(adjective, dull, time, strong, great)
15
prolonged(adjective, strong, great, excite, slow)
13
protracted(adjective, strong, great, excite, difficult)
12
extended(adjective, strong, big, high, large)
11
wordy(adjective, dull, slow, loose, boring)
10
prolix(noun, adjective, dull, slow, loose)
10
verbose(adjective, dull, slow, loose, boring)
10
interminable(adjective, slow, late, long, rambling)
10
long-winded(adjective, dull, slow, loose, boring)
9
drawn-out(adjective, great, excite, slow, high)
9
extensive(adjective, great, big, deep, high)
7
overlong(adjective, great, excite, slow, high)
7
windy(adjective, dull, loose, long, rambling)
7
long-drawn-out(adjective, great, excite, slow, boring)
7
tedious(adjective, slow, boring, long, rambling)
6
diffuse(adjective, slow, boring, tedious, late)
6
dragging(adjective, great, excite, slow, high)
6
elongated(adjective, great, deep, high, remote)
6
endless(adjective, wordy)
6
elongate(adjective, great, deep, high, remote)
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APASmart Define. (2016). lengthy thesaurus. Retrieved September 20, 2026, from https://smartdefine.org/lengthy/thesaurus/synonyms
ChicagoSmart Define. 2016. "lengthy thesaurus" https://smartdefine.org/lengthy/thesaurus/synonyms (accessed September 20, 2026).
HarvardSmart Define 2016, lengthy thesaurus, Smart Define, viewed 20 September, 2026, <https://smartdefine.org/lengthy/thesaurus/synonyms>.
MLASmart Define. "lengthy thesaurus" 26 February 2016. Web. 20 September 2026. <https://smartdefine.org/lengthy/thesaurus/synonyms>