Term: arxhaea, archaebacteria
Origin: Anc Greek
άρχω/archo(=start, lead, rule)
βακτήριον/bacterion(=bacterium) > βακτηρία/bacteria (=rod, stick) because the first ones observed were rod-shaped.
A taxonomic domain of single-celled organisms lacking nuclei like bacteria. It is considered now that archaea are more closely related to eukaryotes than to bacteria mainly because of metabolic similarities. In the past they had been classed with bacteria as prokaryotes (or Kingdom Monera) and named archaebacteria