Green’s Dictionary of Slang

1. (US Und.) to murder; to assassinate.

1949

Monteleone Criminal Sl. (rev. edn).

2. (N.Z. gay) to remove or destroy lights installed in public lavatories used for homosexual pickups.

2007

W. Ings ‘A Convenient Exchange’ in Public Space 3 33: blackout verb: to remove lights installed in or around bogs to increase safety.