amoe·​ba | \ ə-ˈmē-bə How to pronounce amoeba (audio) \
variants: or less commonly
plural amoebas or amoebae also amebas or amebae\ ə-​ˈmē-​(ˌ)bē How to pronounce amebae (audio) \

Definition of amoeba

: any of a large genus (Amoeba) of naked rhizopod protozoans with lobed and never anastomosing pseudopodia, without permanent organelles or supporting structures, and of wide distribution in fresh and salt water and moist terrestrial environments broadly : a naked rhizopod or other amoeboid protozoan

Illustration of amoeba

Illustration of amoeba

amoeba: 1 pseudopodium, 2 nucleus, 3 contractile vacuole, 4 food vacuole

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Other Words from amoeba

amoebic or less commonly amebic \ ə-​ˈmē-​bik \ adjective

Examples of amoeba in a Sentence

Recent Examples on the Web The state Department of Health and Human Resources said in a news release Wednesday that the infection was caused by the amoeba naturally present in warm freshwater during the summer. NBC News, "Brain-eating amoeba kills person who swam in North Carolina manmade lake," 25 July 2019 The amoeba doesn't cause illness if swallowed but can be fatal if forced up the nose during a water activity like diving or water-skiing, officials said. N'dea Yancey-bragg, USA TODAY, "Man dies after contracting 'brain-eating amoeba' at North Carolina water park," 25 July 2019 Oceans In its report last summer, the CDC warned that marine illnesses can come from algal blooms, amoeba and fecal pathogens. Jamie Ducharme, Time, "Your Summer Beach Trip Could Put You at Risk of Getting Sick. Here's What You Need to Know," 24 July 2019 In more ethereal ways, Gabe touched the giant running, jogging, walking, watching amoeba that is called the running community. Tim Layden,, "‘Brave Like Gabe’: Remembering the Runner Who Never Gave Up in the Face of an Unbeatable Opponent," 11 June 2019 The Centers for Disease Control and Prevention says the amoeba is a single-cell living organism commonly found in warm freshwater like lakes and rivers. Amir Vera, CNN, "10-year-old Texas girl contracts brain-eating amoeba while swimming," 14 Sep. 2019 She was successfully treated with amphotericin B, but subsequent lab tests suggested that the invading amoeba was less virulent than other strains of N. fowleri. Beth Mole, Ars Technica, "Brain-eating amoeba kills again—here’s how it kills and how to avoid it," 26 July 2019 Brain-eating amoeba is most commonly found in warm fresh waters such as lakes, rivers and hot springs. Julie Mazziotta,, "A Man Died After Contracting a Brain-Eating Amoeba from a Water Park: What You Need to Know," 26 July 2019 The amoeba can cause severe illness up to nine days after exposure. Leada Gore |, al, "Man dies after contracting brain-eating amoeba after water park visit," 26 July 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'amoeba.' 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 amoeba

1822, in the meaning defined above

History and Etymology for amoeba

New Latin, genus name, from Greek amoibē change, from ameibein to change — more at migrate

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Statistics for amoeba

Last Updated

30 Oct 2019

Time Traveler for amoeba

The first known use of amoeba was in 1822

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More Definitions for amoeba


How to pronounce amoeba (audio)

English Language Learners Definition of amoeba

: a tiny living thing that consists of a single cell


amoe·​ba | \ ə-ˈmē-bə How to pronounce amoeba (audio) \
plural amoebas or amoebae\ -​bē \

Kids Definition of amoeba

: a tiny water animal that is a single cell which flows about and takes in food


amoe·​ba | \ ə-ˈmē-bə\

Medical Definition of amoeba

1 capitalized : a large genus of naked rhizopod protozoans that have lobed and never anastomosing pseudopodia and are widely distributed in fresh and salt water and moist terrestrial environments
2 also ameba plural amoebas or amoebae\ -​(ˌ)bē How to pronounce amoebae (audio) \ also amebas or amebae : a protozoan of the genus Amoeba broadly : an amoeboid protozoan (as a naked rhizopod)

Other Words from amoeba

amebic or amoebic \ -​bik How to pronounce amoebic (audio) \ adjective

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More from Merriam-Webster on amoeba

Rhyming Dictionary: Words that rhyme with amoeba

Spanish Central: Translation of amoeba

Nglish: Translation of amoeba for Spanish Speakers Encyclopedia article about amoeba

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