2
faithfully(adverb, resolutely, tenaciously)
2
grindingly(adverb, difficultly)
2
hardly
2
indefatigably(adverb, resolutely, tenaciously)
2
knottily(adverb, difficultly)
2
onerously(adverb, difficultly)
2
potently(adverb, strongly)
2
rigidly
2
ruggedly(adverb, difficultly)
2
solidly
2
staunchly(adverb, resolutely, tenaciously)
2
tirelessly(adverb, resolutely, tenaciously)
2
toilsomely(adverb, difficultly)
2
trickily(adverb, difficultly)
2
troublesomely(adverb, difficultly)
2
truly(adverb, resolutely, tenaciously)
2
tryingly(adverb, difficultly)
2
with difficulty(expression, idiom)
1
adamantly
1
adversely(adverb, difficultly)
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APASmart Define. (2015). toughly thesaurus. Retrieved September 24, 2026, from https://smartdefine.org/toughly/thesaurus/synonyms
ChicagoSmart Define. 2015. "toughly thesaurus" https://smartdefine.org/toughly/thesaurus/synonyms (accessed September 24, 2026).
HarvardSmart Define 2015, toughly thesaurus, Smart Define, viewed 24 September, 2026, <https://smartdefine.org/toughly/thesaurus/synonyms>.
MLASmart Define. "toughly thesaurus" 14 April 2015. Web. 24 September 2026. <https://smartdefine.org/toughly/thesaurus/synonyms>