To obstruct or block passage on (a road, for example), To halt the motion or progress of, To be or get in the way of (a bullet or other missile); be killed or wounded by, noun_ A device or means that obstructs, blocks, or plugs up, The effective aperture of a lens, controlled by a diaphragm, The act of stopping a string or hole on an instrument, adjective_ Of, relating to, or being of use at the end of an operation or activity