The
Essonne is a long French river. It is a
tributary off the left bank of the
Seine. Its course crosses the departments of
Loiret and
Essonne, and it gives its name to the latter. The Essone's name and the present name of its higher course (the Œuf) originate in
Acionna, a Gallo-Roman river goddess attested at
Orléans (Genabum).