Medical Dictionary
4 ENTRIES FOUND:

aperture

noun ap·er·ture
\ˈap-ə(r)-ˌch(ə)r, -chər, -ˌt(y)(ə)r\

Definition of APERTURE

1
:  an opening or open space
2
:  the diameter of the stop in an optical system that determines the diameter of the bundle of rays traversing the instrument
April 01, 2015
diapause Hear it
a period of physiological dormancy
Take a 3-minute break and test your skills!
How to use a word that (literally) drives some people nuts.
Test your vocab with our fun, fast game
Ailurophobia, and 9 other unusual fears