140 entries under essential topic. ×

44
required(adjective, right, important, capital)
33
requisite(noun, adjective, important, want, need)
29
indispensable(adjective, important, significant, original)
28
vital(adjective, body, material, big, important)
23
obligatory(adjective, sound, right, obligation)
23
fundamental(noun, adjective, body, material, important)
21
imperative(adjective, important, critical, vital)
21
compulsory(adjective, cruel, pitiless, obligation)
21
important(adjective, significant, original, substantial, serious)
20
prerequisite(noun, adjective, important, want, need)
19
unavoidable(adjective, regular, obvious, bound)
18
urgent(adjective, important, substantial, valuable)
17
crucial(adjective, big, important, significant, original)
17
needful(adjective, set, important, original, capital)
17
organic(adjective, important, significant, natural, animate)
16
necessity(noun, want, need, basic)
16
mandatory(adjective, right, obvious, obligation)
15
needed(adjective, important, critical, verb)
13
basic(noun, adjective, body, material, important)
12
key(adjective, important, significant, original)
<123457>
10 years ago|19k views|share |citing 
APASmart Define. (2015). necessary thesaurus. Retrieved September 21, 2026, from https://smartdefine.org/necessary/thesaurus/synonyms
ChicagoSmart Define. 2015. "necessary thesaurus" https://smartdefine.org/necessary/thesaurus/synonyms (accessed September 21, 2026).
HarvardSmart Define 2015, necessary thesaurus, Smart Define, viewed 21 September, 2026, <https://smartdefine.org/necessary/thesaurus/synonyms>.
MLASmart Define. "necessary thesaurus" 2 November 2015. Web. 21 September 2026. <https://smartdefine.org/necessary/thesaurus/synonyms>