[ me-than-uh-juh n, -jen ]
/ mɛˈθæn ə dʒən, -ˌdʒɛn /


any of a diverse group of widely distributed archaebacteria that occur in anaerobic environments, as the intestinal tracts of animals, freshwater and marine sediments, and sewage, and are capable of producing methane from a limited number of substrates, including carbon dioxide and hydrogen, acetate, and methylamines: an important source of natural gas.

Origin of methanogen

1975–80; methane- + -o- + -gen
Related formsmeth·an·o·gen·ic, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Medicine definitions for methanogen


[ mĕ-thănə-jən, -jĕn′ ]


Any of various anaerobic methane-producing bacteria belonging to the family Methanobacteriaceae.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.