orifice
/ɒrˈɪfɪs/Definitions
1. noun
A natural opening or passage in a body or object, especially one that allows the passage of a fluid or gas.
“The doctor examined the orifice of the wound to determine the extent of the injury.”
2. noun
A small opening or passage, especially one that is artificial or man-made.
“The engineer designed a system to control the flow of air through the orifice of the turbine.”