136 entries under tough topic. ×

11
pigheaded(adjective, firm, deliberate, determined)
10
hard(adjective, sharp, firm, fixed)
10
intransigent(adjective, firm, difficult, determined)
10
self-willed(adjective, firm, difficult, determined)
9
implacable(adjective, hard, firm, cruel)
9
obstreperous(adjective, control, order, resist)
9
willful(adjective, firm, difficult, violent)
8
pertinacious(adjective, strong, firm, difficult)
8
stiff(adjective, hard, rough, firm)
7
firm(adjective, persistent, rigid, inflexible)
7
inexorable(adjective, appearance, firm, violent)
7
resolute(adjective, appearance, hard, rough)
7
severe(adjective, persistent, reserved, obstinate)
7
untoward(adjective, control, order, firm)
6
cantankerous(adjective, firm, difficult, persistent)
6
persistent(adjective, firm, determined, obstinate)
6
relentless(adjective, appearance, strong, firm)
6
stiff-necked(adjective, firm, stupid, unreasonable)
6
tenacious(adjective, firm, difficult, persistent)
6
uncompliant(adjective, firm, unreasonable, irritable)
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APASmart Define. (2015). intractable thesaurus. Retrieved September 26, 2026, from https://smartdefine.org/intractable/thesaurus/synonyms
ChicagoSmart Define. 2015. "intractable thesaurus" https://smartdefine.org/intractable/thesaurus/synonyms (accessed September 26, 2026).
HarvardSmart Define 2015, intractable thesaurus, Smart Define, viewed 26 September, 2026, <https://smartdefine.org/intractable/thesaurus/synonyms>.
MLASmart Define. "intractable thesaurus" 24 June 2015. Web. 26 September 2026. <https://smartdefine.org/intractable/thesaurus/synonyms>