keyhole

The hole in a lock where the key is inserted and turns.

Any small opening resembling the hole for a key in shape or function; especially, one that gives a vista of, or access to, a space beyond.

Any small opening resembling the hole for a key in shape or function; especially, one that gives a vista of, or access to, a space beyond.

A circle cut out of a garment as a decorative effect, typically at the front or back neckline of a dress.

A hole or excavation in beams intended to be joined together, to receive the key that fastens them.

To strike a target after wobbling in flight so that the long axis of the bullet does not follow the line of flight, typically due to insufficient spin resulting from the rifling in the barrel.