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bacterium

[ bak-teer-ee-uhm ]
/ bækˈtɪər i əm /
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noun
singular of bacteria.
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Origin of bacterium

1840–50; <New Latin <Greek baktḗrion, diminutive of baktēría staff; akin to báktron stick, Latin baculum, bacillum
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022

How to use bacterium in a sentence

British Dictionary definitions for bacterium

bacterium
/ (bækˈtɪərɪəm) /

noun
the singular of bacteria
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for bacterium

bacterium
[ băk-tîrē-əm ]

Plural bacteria
Any of a large group of one-celled organisms that lack a cell nucleus, reproduce by fission or by forming spores, and in some cases cause disease. They are the most abundant lifeforms on Earth, and are found in all living things and in all of the Earth's environments. Bacteria usually live off other organisms. Bacteria make up most of the kingdom of prokaryotes (Monera or Prokaryota), with one group (the archaea) sometimes classified as a separate kingdom. See also archaeon prokaryote.

Other words from bacterium

bacterial adjective
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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