Wiktionary
n. (context military English) A rapid retreat, a rout. vb. 1 (context idiomatic intransitive English) To leave (a place) hastily (originally military). 2 (context idiomatic intransitive English) to abandon someone without warning. 3 (context idiomatic intransitive English) miss school, play truant, play hooky. 4 (context idiomatic transitive of one's eyes English) To cause to bulge. 5 (context idiomatic computing English) To crash or glitch.
WordNet
Wikipedia
"Bug Out" is a special hour-long episode of M*A*S*H. With North Korean forces on the march, the 4077th must bug out and move the entire camp, but a soldier who has just had serious spinal surgery cannot be moved. Hawkeye, Radar and Margaret stay behind as the rest of the camp tries to set up a new base. Footage from this episode of the 4077th tents being packed up was later recycled in the series finale " Goodbye, Farewell and Amen". During Bug Out, Colonal Potter is offered Rolaids by a Korean trying to sell him land for relocation. The Korean War lasted from 1950 to 1953; Rolaids was not released to the American public until 1953.
Usage examples of "bug out".
At corridor six, Nivry and Jynett had taken a bug out although from nine meters away, it was impossible to tell for certain if it was dead.
So I got the Bug out, locked the doors and set the thermostats, and I set out.
Jenna's hand was shaking as she drew the Shield Bug out of her pocket and raised it up in the air.
If we just happened to kill every bug out there but just left one of them alive, that last one would keep on trying to attack us.
Something tells me he is getting ready to bug out and take all the stuff from the cabinet with him.