A gravitational keyhole.
A mortise for a key or cotter.
Any small opening resembling the hole for a key in shape or function.
A hole or excavation in beams intended to be joined together, to receive the key that fastens them.
A transient column of vapor or plasma formed when using high energy beams, such as lasers, for welding or cutting.
The free-throw lane together with the circle surrounding the free-throw line; key.
The hole in a lock where the key is inserted and turns.
A circle cut out of a garment as a decorative effect, typically at the front or back neckline of a dress.
A welding method in which a hole forms in the surface immediately ahead of the puddle in the direction of welding. The hole is filled as the weld progresses.
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.
An extended region of space containing no galaxies.
An empty place; A location that has nothing useful.
An empty space; a vacuum.
A collection of adjacent vacancies inside a crystal lattice.
A pocket of vapour inside a fluid flow, created by cavitation.
An empty space between floors or walls, including false separations and planned gaps between a building and its facade.
A black cat.
That does not return a value; a procedure.
Containing nothing; empty; not occupied or filled.
Having no incumbent; unoccupied; said of offices etc.
Being without; destitute; devoid.
Containing no immaterial quality; destitute of mind or soul.
Not producing any effect; ineffectual; vain.
Of no legal force or effect, incapable of confirmation or ratification.
To make invalid or worthless.
To throw or send out; to evacuate; to emit; to discharge.
To empty.