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n. pl. ar·chae·bac·te·ri·a


pl n, sing -rium (-rɪəm)
(Microbiology) (formerly) a group of microorganisms now regarded as members of the Archaea. See archaean
[from archaeo- + bacteria]


(ˌɑr ki bækˈtɪər i ə)

also ar•chae•o•bac•te•ri•a

(ˌɑr ki oʊ-), sing. -te•ri•um (-ˈtɪər i əm)
a group of microorganisms, including methanogens and halobacteria, that are genetically and functionally different from all other living forms, thrive in oxygen-poor environments, and are sometimes classified as a separate kingdom.
[1977; < New Latin, =archae-, irreg. for archaeo- archaeo- (perhaps an erroneous Latinizing of Greek arche- arche-) + bacteria bacteria]
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.archaebacteria - considered ancient life forms that evolved separately from bacteria and blue-green algaearchaebacteria - considered ancient life forms that evolved separately from bacteria and blue-green algae
moneran, moneron - organisms that typically reproduce by asexual budding or fission and whose nutritional mode is absorption or photosynthesis or chemosynthesis
division Archaebacteria - in some classifications considered a kingdom
methanogen - archaebacteria found in anaerobic environments such as animal intestinal tracts or sediments or sewage and capable of producing methane; a source of natural gas
halophil, halophile - archaebacteria requiring a salt-rich environment for growth and survival
thermoacidophile - archaebacteria that thrive in strongly acidic environments at high temperatures
References in periodicals archive ?
Archaea and Eubacteria have one kingdom within them each: archaebacteria and eubacteria.
Many genes that contribute to Galdieria's adaptations were not inherited from its ancestor red algae, but were acquired from bacteria or archaebacteria.
17; Clan CA, family C02), which are found in almost all eukaryotes and a few bacteria but not in archaebacteria (Croall and Demartino, 1991; Goll et al.
Protein Phylogenetics and Signature Sequences: A Reappraisal of Evolutionary Relationship Among Archaebacteria, Eubacteria, and Eukaryotes.
Prokarya would include two kingdoms: Eubacteria and Archaebacteria
Protein phylogenies and signature sequences: a reappraisal of evolutionary relationships among archaebacteria, eubacteria, and eukaryotes.
Carl Woese and George Fox publish a paper in PNAS identifying the third domain of life, the archaebacteria (now commonly called Archaea).