[ahr-kee-bak-teer-ee-uh m] /ˌɑr ki bækˈtɪər i əm/ (Show IPA)
1.
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, archaeobacteria
[ahr-kee-oh-bak-teer-ee-uh] /ˌɑr ki oʊ bækˈtɪər i ə/ (Show IPA).
Origin
1977; < Neo-Latin, equivalent to archae-, irregular for archaeo-archaeo- (perhaps an erroneous Latinizing of Greekarche-arche-) + bacteriabacteria
British Dictionary definitions for archaebacterium
archaebacteria
/ˌɑːkɪbækˈtɪərɪə/
plural noun
1.
(formerly) a group of microorganisms now regarded as members of the ArchaeaSee archaean
Word Origin
from archaeo- + bacteria
Word Origin and History for archaebacterium
archaebacteria
n.
plural of archaebacterium (1977), from archaeo- + bacterium (see bacteria).
archaebacterium in Science
archaebacterium
(är'kē-bāk-tîr'ē-əm) Pluralarchaebacteria See archaeon.