Auxiliary and Indispensable

Auxiliary

Auxiliary adjective - Available to supply something extra when needed.
Usage example: the auditorium has an auxiliary cooling system used only on particularly sweltering days

Indispensable is an antonym for auxiliary.

Indispensable

Indispensable adjective - Impossible to do without.

Auxiliary is an antonym for indispensable in necessary topic.

Nearby Word: indispensably
Cite this Source
Indispensable and Auxiliary. (2016). Retrieved 2026, July 21, from https://thesaurus.plus/related/auxiliary/indispensable
Auxiliary & Indispensable. N.p., 2016. Web. 21 Jul. 2026. <https://thesaurus.plus/related/auxiliary/indispensable>.
Indispensable or Auxiliary. 2016. Accessed July 21, 2026. https://thesaurus.plus/related/auxiliary/indispensable.
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