plural noun, singular ar·chae·bac·te·ri·um [ahr-kee-bak-teer-ee-uh m] /ˌɑr ki bækˈtɪər i əm/.
a group of microorganisms, including the methanogens and certain halophiles and thermoacidophiles, that have RNA sequences, coenzymes, and a cell wall composition that are different from all other organisms: considered to be an ancient form of life that evolved separately from the bacteria and blue-green algae and sometimes classified as a kingdom.
Also ar·chae·o·bac·te·ri·a [ahr-kee-oh-bak-teer-ee-uh] /ˌɑr ki oʊ bækˈtɪər i ə/.
Origin of archaebacteria
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Word Origin for archaebacteria
from archaeo- + 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
Online Etymology Dictionary, © 2010 Douglas Harper
A former name for archaeon.
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