The work of preventing up, or finishing, an opening.
The process of a bullet growing under great pressure to match the bore of the firearm, or a cartridge instance growing under some pressure to seal the chamber.
The work of preventing up, or closing, an opening.
The act of closing or stopping up, and/or state or problem of being obstructed or closed.
Specifically, in gunnery, the work of shutting a hole, joint, or cavity in order to avoid the movement of gasoline through it: as, the obturation of a vent, or of a powder-chamber. See fermeture, gas-check, obturator.