Air opening (4)
I believe the answer is:
vent
(Other definitions for vent that I've seen before include "Airhole" , "Orifice" , "Opening for air" , "Small outlet" , "Voice" .)
I believe the answer is:
vent
(Other definitions for vent that I've seen before include "Airhole" , "Orifice" , "Opening for air" , "Small outlet" , "Voice" .)