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C.O.
C.O. /ˌsiː ˈəʊ◂ $ -ˈoʊ◂/
noun [countable]
(Commanding Officer) an officer who is in charge of a military unit
C.O. /ˌsiː ˈəʊ◂ $ -ˈoʊ◂/
noun [countable](Commanding Officer) an officer who is in charge of a military unit