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peptococcus

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noun pep·to·coc·cus \ˌpep-tə-ˈkäk-əs\

Medical Definition of peptococcus

  1. 1 capitalized :  a genus of anaerobic gram-positive coccal bacteria that do not form spores and are now considered to comprise a single species (P. niger)

  2. 2plural peptococci \-ˈkäk-ˌ(s)ī\play play :  any bacterium of the genus Peptococcus

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