Chat Moss may be named after St Chad, a 7th-century bishop of Mercia, but as it was once part of a great tree-edged lake, as evidenced by the numerous wood remains in the lower levels of the peat, it is perhaps more likely that the name stems from the Celtic word "ced", meaning wood. Chat Moss could also derive from Ceatta, an Old English personal name and "mos", a swamp or alternatively the first element could be the Old English "ceat" meaning a piece of wet ground. It was recorded as Catemosse in 1277 and Chatmos in 1322. "Moss" is the local name for a peat bog.