archaebacteria: Meaning and Definition of

ar•chae•bac•te•ri•a

Pronunciation: (är"kē-bak-tēr'ē-u), [key]
— sing. -te•ri•um
  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.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.
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