Definitions
1.NounA small hole, of a size that could have been made by a pin
2.NounThe aperture in a pinhole camera or camera obscura
3.NounA port left unprotected by a firewall to allow a particular application to gain access to a service.
4.Noun(meteorology) A clipping of pinhole eye, which refers to the compact eye structure associated with intense tropical cyclones.
5.VerbTo form one or more pinholes in.