manganese dioxide


: a dark insoluble compound MnO2 used especially as an oxidizing agent, as a depolarizer of dry cells, and in making glass and ceramics

Example Sentences

Recent Examples on the Web When attached at either end to a circuit such as a light bulb, the zinc inside reacts with the manganese dioxide and loses electrons. Manasee Wagh, Popular Mechanics, 13 May 2022 For example, an alkaline battery, or cell, contains zinc, manganese dioxide, and potassium hydroxide. Manasee Wagh, Popular Mechanics, 13 May 2022 In the future, the photographer plans to test out more exotic thermites like bismuth trioxide and manganese dioxide. Wired, 31 Oct. 2019

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

Word History

First Known Use

1866, in the meaning defined above

Time Traveler
The first known use of manganese dioxide was in 1866

Dictionary Entries Near manganese dioxide

Cite this Entry

“Manganese dioxide.” Dictionary, Merriam-Webster, Accessed 29 Nov. 2022.

Kids Definition

manganese dioxide


: a dark compound of manganese and oxygen that is used especially in making glass and ceramics
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