'Hanwell' probably means the spring or stream frequented by cocks.
It was recorded in 959 as Hanewelle, when a Saxon called Alfwyn pawned his land to go on a pilgrimage. The origin is uncertain: another idea links Han to a boundary stone, and a stone weighing about a ton lies near Hanwell spring. The station was called Hanwell and Elthorne from 1896 to 1974.