noun

• (architecture) The arrangement of windows and similar openings in a building.
• (surgery, anatomy) An opening in the surface of an organ etc; the surgical creation of such an opening, especially one in the bony part of the inner ear made to improve hearing.
• (surgery, anatomy) An opening that occurs naturally or is created surgically, as through a biological membrane.
• (botany) Either a translucent area in a structure such as a leaf or flower petal, or an opening in a structure.
• (nautical) The practice of placing holes in the rudder of a ship to reduce the work required to move the rudder while preserving its ability to steer the ship.