camera, photographic camera - equipment for taking photographs (usually consisting of a lightproof box with a lens at one end and light-sensitive film at the other)

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

telescope, scope - a magnifier of images of distant objects

eye, oculus, optic - the organ of sight

pupil - contractile aperture in the iris of the eye

hole - an opening into or through something

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

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

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; "the mouthpiece of a respirator"

opening - a vacant or unobstructed space that is man-made; "they left a small opening for the cat at the bottom of the door"