PVC fittings may either have spigot or socket end connections. A spigot end is the equivalent of a male end, and a socket end is the equivalent of a female end. A spigot end fits into a socket end.

PVC pipe has spigot ends and must connect to socket connections on both ends. PVC Fittings have either connections and allow connection to either PVC pipe or another PVC Fitting.

Also in a situation where you need to connect pipe to a fitting or slip T that is too large, you can use a reducer bushing to scale the socket end down to fit the spigot.