The condition or feeling of being safe; security; certainty.

“If you push it to the limit, safety is not guaranteed.”

A mechanism on a weapon or dangerous equipment designed to prevent accidental firing.

“Be sure that the safety is set before proceeding.”

An instance of a player being sacked or tackled in the end zone, or stepping out of the end zone and off the field, resulting in two points to the opposite team.

“He sacked the quarterback in the end zone for a safety.”

To secure (a mechanical component, as in aviation) to keep it from becoming detached even under vibration.

To secure a firing pin, as in guns, to keep the gun from firing