bacterium

play
noun bac·te·ri·um \bak-ˈtir-ē-əm\

Definition of bacterium

plural

-ria

\-ē-ə\
  1. :  any of a domain (Bacteria) of prokaryotic round, spiral, or rod-shaped single-celled microorganisms that may lack cell walls or are gram-positive or gram-negative if they have cell walls, that are often aggregated into colonies or motile by means of flagella, that typically live in soil, water, organic matter, or the bodies of plants and animals, that are usually autotrophic, saprophytic, or parasitic in nutrition, and that are noted for their biochemical effects and pathogenicity; broadly :  prokaryote — compare archaea, eukaryote

Origin and Etymology of bacterium

New Latin, from Greek baktērion staff


First Known Use: circa 1849

Other Microbiology Terms


BACTERIUM Defined for English Language Learners

bacterium

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noun bac·te·ri·um \bak-ˈtir-ē-əm\

Definition of bacterium for English Language Learners

  • : any one of a group of very small living things that often cause disease


BACTERIUM Defined for Kids

bacterium

play
noun bac·te·ri·um \bak-ˈtir-ē-əm\

Definition of bacterium for Students

plural

bacteria

\-ē-ə\
  1. :  any of a group of single-celled microscopic organisms that are important to humans because of their chemical activities and as causes of disease


Medical Dictionary

bacterium

play
noun bac·te·ri·um \bak-ˈtir-ē-əm\

Medical Definition of bacterium

plural

bacteria

\-ē-ə\play
  1. :  any of a domain (Bacteria) of prokaryotic round, spiral, or rod-shaped single-celled microorganisms that may lack cell walls or are gram-positive or gram-negative if they have cell walls, that are often aggregated into colonies or motile by means of flagella, that typically live in soil, water, organic matter, or the bodies of plants and animals, that are usually autotrophic, saprophytic, or parasitic in nutrition, and that are noted for their biochemical effects and pathogenicity; broadly :  prokaryote



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