1A soldier in a blue uniform, especially a Union soldier during the Civil War.
- ‘She had taken many lives, in the name of the blue coats, of course, but still, she did everything he told her to, so she was no threat to him.’
- 1.1US A police officer.
- ‘‘You know me, officer,’ he said, as the blue coat came running in. ‘I give this man into custody for theft.’’
- ‘The blue-coat came on slowly, expecting gunfire from a cornered criminal.’