Ouse

River in northern England; length 87 km/54 mi. It is formed by the junction of the rivers Ure and Swale near Boroughbridge in North Yorkshire and flows in a southeasterly direction through York City and the East Riding of Yorkshire to unite with the Trent 13 km/8 mi east of Goole. The two rivers then form the Humber.

The chief tributaries are the Nidd, Wharfe, Aire, and Don from the northwest, and the Derwent from the northeast. Navigation on the Ouse is connected via the Aire and Calder to Leeds and Dewsbury.

Ouse

River in southeast England; length 48 km/30 mi; it rises between Horsham and Cuckfield in the Weald of West Sussex and flows southwards through the South Downs to enter the English Channel at Newhaven. Uckfield and Lewes are the principal towns on its banks. The River Uck is its only main tributary.

The Sussex Ouse derives its name from the town of Lewes, the river being known in early charters as aqua de Lewes, later misunderstood as ‘de l'Ouse’.