skating on shell casings
Slang for being extremely busy, having been extremely busy or both.
Busy person (picking up phone): "What !?! This had better be good! I am skating on shell casings here, you know!"
Caller: "The boss wants the names of who we are sending to the hazardous materials training."
Busy Person: "Yeah, I'll get right on that"
Caller: "The boss wants the names of who we are sending to the hazardous materials training."
Busy Person: "Yeah, I'll get right on that"