aperture has definitions from the field of photography
1
[ noun ] (photography) a device that controls amount of light admitted

Used in print

(1961 Research Highlights of the National Bureau of...)

The shutter aperture may be made larger or smaller by changing the foil area and adjusting the electrical energy input to the foil .

Related terms

regulator camera telescope

2
[ noun ] an opening in something

Related terms

hole pupil micropyle stoma eye

3
[ noun ] an opening; usually small

Related terms

opening mouthpiece mouthpiece

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