unreactive

adjective

un·​re·​ac·​tive ˌən-rē-ˈak-tiv How to pronounce unreactive (audio)
: not tending to react : not reactive
pupils unreactive to light
chemically unreactive solvents

Examples of unreactive in a Sentence

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Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The intense, self-dramatizing Em and the unmoored but also unreactive and unironic Rohit are married but maybe not for much longer. — Sara Holdren, Vulture, 27 Mar. 2024 And the mirrors of the JWST are gilded with gold, an element useful for its unreactive nature and ability to reflect infrared light (not to mention its popularity in jewelry). — Sanjana Curtis, Scientific American, 12 Dec. 2022

Word History

First Known Use

1832, in the meaning defined above

Time Traveler
The first known use of unreactive was in 1832

Rhymes for unreactive

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unreactive
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“Unreactive.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/unreactive. Accessed 25 Mar. 2025.

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Medical Definition

unreactive

adjective
un·​re·​ac·​tive -rē-ˈak-tiv How to pronounce unreactive (audio)
: not reactive
pupils unreactive to light
an unreactive gas
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