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n. The part of the lock which is moved when the key is engaged.

n. A kind of lock in which the bolt (moving portion) is held in position by the cylinder rather than by a spring and so can not be retracted except by turning the cylinder.

v. To fasten or secure with a deadbolt.

n. the part of a lock that is engaged or withdrawn with a key

"That way if somebody was to break the glass and reach inside, they couldn't unlock your deadbolt, which is what happens a lot of times."

bar   

safety lock    safety bolt   

dead-bolt    key-operated    carabiner    aft-motion    saddle-horn