What is the relationship between Al-Kawthar and the Basin (Hawd) to which Muslims will come on the Day of Resurrection, and is Al-Kawthar a reference to it?

Al-Kawthar is a river in Paradise that Allah bestowed upon the Prophet, peace and blessings be upon him. As for the Hawd (Cistern), it is outside Paradise, and Muslims will approach it before entering Paradise. Its water is supplied from Al-Kawthar.