4
greatly
4
heart and soul(expression, idiom, resolution)
4
heavily(adverb, fast, sprightly, severely, intensely)
4
resolutely(adverb, resolution)
4
significantly(adverb, urgently, importantly)
4
staidly
3
actively(adverb, fast, sprightly, severely, intensely)
3
candidly
3
demurely
3
devoutly
3
disadvantageously
3
hard(adverb, fast, badly, severely, intensely)
3
heartily(adverb, sincerely)
3
intently
3
passionately(adverb, severely, thoroughly, completely, extremely)
3
purposefully(adverb, thoroughly, vigorously, earnestly, actively)
3
sadly(adverb, severely, thoroughly, completely, affirmation)
3
sedately
3
somberly(adverb, sadly, grimly, sternly, sorrowfully)
3
vigorously(adverb, fast, intensely, fiercely, earnestly)
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APASmart Define. (2016). seriously thesaurus. Retrieved September 23, 2026, from https://smartdefine.org/seriously/thesaurus/synonyms
ChicagoSmart Define. 2016. "seriously thesaurus" https://smartdefine.org/seriously/thesaurus/synonyms (accessed September 23, 2026).
HarvardSmart Define 2016, seriously thesaurus, Smart Define, viewed 23 September, 2026, <https://smartdefine.org/seriously/thesaurus/synonyms>.
MLASmart Define. "seriously thesaurus" 31 March 2016. Web. 23 September 2026. <https://smartdefine.org/seriously/thesaurus/synonyms>