77 entries under significant topic. ×

32
essential(noun, adjective, form, fix, pass)
21
urgent(adjective, strong, firm, prompt, big)
21
important(adjective, substantial, serious, valuable)
20
indispensable(adjective, important, serious, essential)
19
requisite(noun, adjective, important, need)
18
pressing(adjective, firm, prompt, big, important)
17
obligatory(adjective, important, essential, basic)
16
crucial(adjective, big, important, determined)
16
required(adjective, important, essential, critical)
15
critical(adjective, big, important, determined)
13
vital(adjective, big, important, substantial)
13
exigent(adjective, firm, prompt, big, important)
12
compulsory(adjective, set, important, essential)
11
prerequisite(noun, adjective, form, fix, pass)
11
mandatory(adjective, set, essential, basic)
10
needful(adjective, set, important, capital)
10
compelling(adjective, strong, important, serious)
8
binding(adjective, essential, basic, vital)
6
fundamental(noun, adjective, law, regulation, concern)
6
importunate(adjective, firm, prompt, big, important)
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APASmart Define. (2015). imperative thesaurus. Retrieved September 21, 2026, from https://smartdefine.org/imperative/thesaurus/synonyms
ChicagoSmart Define. 2015. "imperative thesaurus" https://smartdefine.org/imperative/thesaurus/synonyms (accessed September 21, 2026).
HarvardSmart Define 2015, imperative thesaurus, Smart Define, viewed 21 September, 2026, <https://smartdefine.org/imperative/thesaurus/synonyms>.
MLASmart Define. "imperative thesaurus" 10 April 2015. Web. 21 September 2026. <https://smartdefine.org/imperative/thesaurus/synonyms>