polymyxinPronunciation: /ˌpɒlɪˈmɪksɪn/Definition of polymyxin noun Medicine any of a group of polypeptide antibiotics that are active chiefly against Gram-negative bacteria. Polymyxins are obtained from soil bacteria of the genus Bacillus, in particular B. polymyxa Origin: 1940s: from modern Latin polymyxa, from Greek polu- 'much' + muxa 'slime' + -in1polymyxin in other Oxford dictionaries Definition of polymyxin in the US English dictionary
