'Highbury' means the high manor; 'Islington' means the hill of a man called Gisla.
Islington was recorded as Giseldone in 1005 and Gislandune in 1062, from the Old English personal name Gisla and dun, a hill; it was still Isledon in the 17th century. A new manor house built on a hill in 1271 was called Highbury. The station opened in 1850 as Islington and took its double name in 1872.