master key

Why it's important: Your SSN is a master key to your financial life.

Fitzwater has also become a member of Crohn's and Colitis UK, who have given him a special card and a master key which allows him to access more than 9,000 locked public toilets.

A maintenance worker gave police a master key to enter the apartment after nobody answered their knocks.

He is still struggling to master key strategic weapons, chiefly a spy satellite and a nuclear-armed submarine.

Leidos told Congress in December it would install peepholes on dorm room doors, limit access to master keys that could open multiple bedrooms, and give teams in the field an extra satellite phone.