Anaerobe

Part of speech: noun

Pronunciation: /ˈænəˌɹoʊb/

Definitions

1. an organism that lives and thrives without requiring oxygen for respiration or survival
2. a life form capable of metabolizing and functioning in environments completely devoid of oxygen
3. a microorganism or creature that obtains energy through non-oxygen-dependent chemical processes

Etymology: The word "anaerobe" is built from Greek roots: the prefix "an-", meaning "without", and "aer", meaning "air", with "bios", meaning "life", giving a sense of "life without air." The core idea is that these organisms thrive where oxygen is absent. It reached English by way of French "anaérobie", the adjective and noun form that French coined for this type of life. The same family of terms gave English the adjective "anaerobic," and the noun "anaerobe" follows the pattern of other scientific words ending in "-obe," which were coined in the nineteenth and twentieth centuries from classical materials rather than handed down from ancient Greek usage. The key sense is a shift from a general notion of living without air to a precise description of how an organism gets its energy. Oxygen is a common byproduct of many energy-producing reactions, so the term identifies organisms whose chemistry runs without it, a meaning that depends on modern biology rather than on the older Greek vocabulary.

Synonyms: microbe, bacterium, organism, germ, pathogen

Antonyms: aerobe, oxygen-dependent organism, aerobic organism, oxidizer, oxidative organism