un·​re·​ac·​tive | \ ˌən-rē-ˈak-tiv How to pronounce unreactive (audio) \

Definition of unreactive

: not tending to react : not reactive pupils unreactive to light chemically unreactive solvents

Examples of unreactive in a Sentence

Recent Examples on the Web These are the types of lasers that are best suited to photonics applications that need to use inert materials—oxides are very unreactive—and need to be small. Chris Lee, Ars Technica, "Wireless nanowire lasers absorb infrared, emit blue light," 1 June 2019 Although nitrogen is the most abundant element in air, the molecular form of nitrogen found there is largely unreactive. Diana Gitig, Ars Technica, "Plants repeatedly got rid of their ability to obtain their own nitrogen," 27 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'unreactive.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of unreactive

1832, in the meaning defined above

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Time Traveler for unreactive

Time Traveler

The first known use of unreactive was in 1832

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Cite this Entry

“Unreactive.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., https://www.merriam-webster.com/dictionary/unreactive. Accessed 11 December 2019.

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More Definitions for unreactive


un·​re·​ac·​tive | \ -rē-ˈak-tiv How to pronounce unreactive (audio) \

Medical Definition of unreactive

: not reactive pupils unreactive to light an unreactive gas

Comments on unreactive

What made you want to look up unreactive? Please tell us where you read or heard it (including the quote, if possible).


heavy with or as if with moisture

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