The Street Elbow
The Street Elbow... where did it get its name?
Back in the day (and even to this day) the water main running down your street had a TEE fitting in front of each house, from which the supply could be tapped in order to supply water to the home. The natural geometry of things dictated that the supply pipe for each house came off at a 90-degree angle from the main, and a pipe (of typically smaller diameter than that of the main itself) should be fitted to the house. It was only natural, therefore, that the elbow fitting used for this purpose would have a male thread to screw into the [upward- or downward-oriented] tap of the tee in the main, and a female fitment facing toward the house, into which the house's supply pipe could be fitted.
Thus we have the "Street Elbow." It's a male-to-female elbow, and it's out there at the edge of the street, doing it's job, 24-seven, bringing water to your home.
The Street Elbow. Every street has them.