n. A microorganism supposed to act like a ferment in causing or propagating certain infectious or contagious diseases; a pathogenic bacterial organism.
the GNU version of the Collaborative International Dictionary of English
n. A microörganism which is supposed to act like a ferment in causing or propagating certain infectious or contagious diseases; a pathogenic bacterial organism.
The Century Dictionary and Cyclopedia
n. One of a class of extremely small living creatures, existing in the atmosphere, and furnishing the basis on which certain epizoötic, epidemic, and other zymotic diseases are dependent for their existence; a zymotic microbe.