mi·​crobe | \ˈmī-ˌkrōb \

Definition of microbe 

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Other Words from microbe

microbial \ mī-​ˈkrō-​bē-​əl \ or less commonly microbic \ -​bik \ adjective

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A hint of the Greek word bios, meaning "life", can be seen in microbe. Microbes, or microorganisms, include bacteria, protozoa, fungi, algae, amoebas, and slime molds. Many people think of microbes as simply the causes of disease, but every human is actually the host to billions of microbes, and most of them are essential to our life. Much research is now going into possible microbial sources of future energy; algae looks particularly promising, as do certain newly discovered or created microbes that can produce cellulose, to be turned into ethanol and other biofuels.

Examples of microbe in a Sentence

Recent Examples on the Web

Materials with Green Art Workshop Make your own insects, plankton, microbes, and other tiny beings with Green Art Workshop. SFChronicle.com, "Kids listings," 12 July 2018 This restoration approach means finding the strongest individuals and breeding them, but also training them to get used to certain stressors or strengthening the supportive microbes, like algae, living in their tissues. Joanna Klein, New York Times, "This Coral Must Die," 25 June 2018 The 2018 emoji, initially announced in February, also include a woman's flat shoe, a pirate flag, a tooth, a bone, toilet paper, a microbe, a peacock, badger, raccoon, swan, salt, skateboard and more. Melinda Morris, NOLA.com, "New emoji: redheads, mosquito and a sweaty, hot face," 1 June 2018 Tweak those constants another way, and stars would burn themselves out so quickly that there would have been no time for the evolution of microbes, dinosaurs, or you. NBC News, "Could alien life exist in parallel universes?," 28 May 2018 The new species include microbes, plants, animals and even the confirmation of an extinct marsupial, based on its fossil. Ashley Strickland, CNN, "Meet the top 10 new species of 2018," 23 May 2018 Many organisms, including microbes, plants and animals have evolved ways to guard themselves. Yousong Ding, Washington Post, "Hawaii is set to ban sunscreens that damage coral. Greener, safer options are on the horizon.," 9 May 2018 This migration can transport heat, nutrients, microbes, and carbon downward. Elizabeth Pennisi, Science | AAAS, "Tiny shrimp may be mixing ocean water as much as the wind and waves," 18 Apr. 2018 Successful organic gardeners rely on compost to improve soil fertility and moisture management, nourish helpful microbes, and inoculate against destructive ones. The Editors Of Organic Life, Good Housekeeping, "How To Build The Ultimate Compost Bin," 16 Mar. 2017

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

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First Known Use of microbe

1878, in the meaning defined above

History and Etymology for microbe

International Scientific Vocabulary micr- + Greek bios life — more at quick entry 1

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Statistics for microbe

Last Updated

5 Nov 2018

Look-up Popularity

Time Traveler for microbe

The first known use of microbe was in 1878

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More Definitions for microbe



English Language Learners Definition of microbe

: an extremely small living thing that can only be seen with a microscope


mi·​crobe | \ˈmī-ˌkrōb \

Kids Definition of microbe

: a very tiny and often harmful living thing : microorganism


mi·​crobe | \ˈmī-ˌkrōb \

Medical Definition of microbe 

: microorganism, germ used especially of pathogenic bacteria

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something that serves to warn or remind

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