Pronunciation: (bak-tēr'ē-u), [key]
—sing. -te•ri•umPronunciation: (-tēr'ē-um). [key]
ubiquitous one-celled organisms, spherical, spiral, or rod-shaped and appearing singly or in chains, comprising the Schizomycota, a phylum of the kingdom Monera (in some classification systems the plant class Schizomycetes), various species of which are involved in fermentation, putrefaction, infectious diseases, or nitrogen fixation.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.