desertionPronunciation: /dɪˈzəːʃn/Translate desertion | into German | into Italian | into Spanish Definition of desertion noun [mass noun] the action of deserting a person, cause, or organization:her guilt over her desertion of her husband Military the action of illegally leaving the armed forces:three officers were shot for desertion [count noun]:the number of desertions was risingdesertion in other Oxford dictionaries Definition of desertion in the US English dictionary