The 'switch' is what you are looking for, I believe. I have seen them listed before as a "switch/sender". The sensor is the coolant temperature sensor which connects to the ECU and has nothing to do with the temperature gauge.
Be aware that Ford has 2 different parts listed for this, the difference being the connector. When I replaced mine none of the stores I went to had the right one and I ended up having to order one from the dealership. Even then they had to order both for me so I could see which one would fit.
