archaebacterium

noun

ar·chae·bac·te·ri·um ˌär-kē-ˌbak-ˈtir-ē-əm

: any of the microorganisms comprising the archaea : archaean

Note: The archaea were originally classified with the bacteria. They have since been placed in their own domain, and use of the term archaebacterium is now typically considered outmoded.

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“Archaebacterium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.grautoblog.com/dictionary/archaebacterium. Accessed 28 Apr. 2026.

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archaebacterium

noun

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