Another curious airline slang phrase is a flight attendant doing a "crotch watch."
... Just as different professionals have their own languages when they communicate with one another, there are also code words that flight attendants use while on duty. Among such terms, the one that often surprises passengers if they hear it is "crotch watch."
This indelicate term is the informal name flight attendants use when they want to check whether passengers have their seatbelts correctly fastened.
Before any takeoff, landing, or when turbulence is expected, flight attendants walk through the cabin and briefly scan each row. When they do this, they're checking whether your seatbelt is buckled, visible, and worn properly.
The crew call this quick scan "crotch watch" because, as flight attendants often tell you, a seatbelt worn correctly sits low and tight across the hips (not the belly).
This task is also sometimes called a "groin scan," and usually happens right after the fasten-seatbelt sign turns on. While the sign is the official instruction to passengers, airlines still prefer that flight attendants visually check for compliance.
This is because they believe the ultimate safety of their passengers solely rests on their shoulders, so they won't want to take any risk.
Besides that flight attendants observe so many things about you the moment you board a plane, this "groin scan" routine is one of the most basic and important safety checks they perform in the cabin.
Why flight attendants take crotch watch seriously ...