aperture

/ˈæpərtʃər/

/ˈæpətʃə/

Other forms: apertures

An aperture is an opening, usually a small one. “If you can thread the silk through that aperture and pull it out the other side, we can knot it and create a loop.”

The most common place you’ll find aperture is when you’re talking about cameras or photography. In that case, an aperture refers specifically to the hole or opening in the lens that lets light through, which you can adjust (with the f-stop) to let in more or less light, resulting in a shallow or deep range of focus. A large aperture means only one tiny point of the photo will be in sharp focus, while a small aperture means that much of the background as well as the foreground will be in focus.

Definitions of aperture

1. noun

   a natural opening in something
   types:

   pupil

   the contractile aperture in the center of the iris of the eye; resembles a large black dot

   micropyle

   minute opening in the wall of an ovule through which the pollen tube enters

   pore, stoma, stomate

   a minute epidermal pore in a leaf or stem through which gases and water vapor can pass

   germ pore

   a pore in the outer wall of a spore or pollen grain through which the germ tube or pollen tube makes its exit on germination

   hydathode, water pore, water stoma

   a pore that exudes water on the surface or margin of a leaf of higher plants

   lenticel

   one of many raised pores on the stems of woody plants that allow the interchange of gas between the atmosphere and the interior tissue

   type of:

   hole

   an opening into or through something
2. noun

   a man-made opening; usually small
   types:

   embouchure, mouthpiece

   the aperture of a wind instrument into which the player blows directly

   mouthpiece

   a part that goes over or into the mouth of a person

   type of:

   opening

   a vacant or unobstructed space that is man-made
3. noun

   a device that controls amount of light admitted
   type of:

   regulator

   any of various controls or devices for regulating or controlling fluid flow, pressure, temperature, etc.