ac·​ti·​no·​my·​cete ˌak-(ˌ)ti-nō-ˈmī-ˌsēt How to pronounce actinomycete (audio)
: any of an order (Actinomycetales) of filamentous or rod-shaped bacteria (such as the actinomyces and streptomyces)

Word History


taken as singular of New Latin Actinomycetes, plural of Actinomyces actinomyces

First Known Use

1883, in the meaning defined above

Time Traveler
The first known use of actinomycete was in 1883

Dictionary Entries Near actinomycete

Cite this Entry

“Actinomycete.” Dictionary, Merriam-Webster, Accessed 4 Dec. 2023.

Medical Definition


ac·​ti·​no·​my·​cete -ˈmī-ˌsēt How to pronounce actinomycete (audio) -mī-ˈsēt How to pronounce actinomycete (audio)
: a bacterium (as an actinomyces or a streptomyces) of the order Actinomycetales see actinomycosis
actinomycetous adjective

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