Concealed orifice Synonyms

Definitions for Concealed

(adjective) not accessible to view
(adjective) hidden on any grounds for any motive

CO abbreviation

CO is an abbreviation for Concealed Orifice

What does CO stand for?

CO stands for "Concealed Orifice"

Orifice replaced

concealed passage

concealed door

Definitions for Orifice

(noun) a place in a surface allowing passage into or through a thing
(noun) an aperture or hole that opens into a bodily cavity