amoeba

play

noun amoe·ba \ə-ˈmē-bə\

variants: or less commonly

ameba

Definition of amoeba

plural

amoebas

amoebae

play \-(ˌ)bē\

: 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

amoebic

play or less commonly

amebic

\-bik\ adjective

See amoeba defined for English-language learners

See amoeba defined for kids

Recent Examples of amoeba from the Web

The amoeba is transferred to victims, the CDC reports, through water entering the nose while swimming in warm lakes and rivers.

— tim evans, USA TODAY, "Who's to blame for lake's brain-eating amoeba? Appeals court wades into negligence lawsuit", 23 June 2017
Water samples taken from the whitewater center after her death tested positive for the amoeba.

— leada gore, AL.com, "67 Alabama counties, ranked from most to least-populated", 21 June 2017
The amoeba won't infect a person who drinks or swallows water containing it, and must enter the body through the nose to cause harm.

— CBS News, "Family files lawsuit over brain-eating amoeba death", 20 June 2017
In June 2016, 18-year-old Lauren Seitz tragically died after contracting a brain-eating amoeba during a visit to a popular North Carolina water park.

— rose minutaglio, PEOPLE.com, "Family of Ohio Teen Who Died From Brain-Eating Amoeba Sues Water Park", 20 June 2017
The amoeba is commonly found in warm freshwater and soil, according to the Centers for Disease Control and Prevention.

— amanda watts, CNN, "Family of teen who died from brain-eating amoeba sues water park", 20 June 2017
The amoeba can also live in swimming pools that aren't being properly maintained.

— Fox News, "Brain-eating amoeba: What is it, and how do you prevent contracting it?", 20 June 2017
The lawsuit says Seitz contracted the amoeba after she was thrown overboard while whitewater rafting at the park.

— CBS News, "Family files lawsuit over brain-eating amoeba death", 20 June 2017
The scientific term for the amoeba Seitz contracted is primary amebic meningoencephalitis, an infection caused by Naegleria fowleri, which is an organism that does not cause illness if swallowed, but can be fatal if forced up the nose.

— rose minutaglio, PEOPLE.com, "Family of Ohio Teen Who Died From Brain-Eating Amoeba Sues Water Park", 20 June 2017

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.

Illustration of amoeba

Origin and Etymology of amoeba

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

NEW!

First Known Use: 1822

See Words from the same year

AMOEBA Defined for English Language Learners

amoeba

play

noun

Definition of amoeba for English Language Learners

: a tiny living thing that consists of a single cell

AMOEBA Defined for Kids

amoeba

play

noun amoe·ba \ə-ˈmē-bə\

Definition of amoeba for Students

plural

amoebas

amoebae

\-bē\

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

Medical Dictionary

amoeba

noun 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\ play : a protozoan of the genus Amoeba; broadly : an amoeboid protozoan (as a naked rhizopod)