Loved:

Blue juice: The water in the lavatory toilet. “There’s no blue juice in the lav.”
Crotch watch: The required check to make sure all passengers have their seat belts fastened. Also: “groin scan.”

Crumb crunchers: Kids. “We’ve got a lot of crumb crunchers on this flight.”

Deadheading: When an airline employee flies as a passenger for company business.

Gate lice: The people who gather around the gate right before boarding so they can be first on the plane. “Oh, the gate lice are thick today.”

George: Autopilot. “I’ll let George take over.”

Landing lips: Female passengers put on their “landing lips” when they use their lipstick just before landing.