'Onion' was a British two-part radio deception within 'Fortitude North' designed to persuade the Germans that the Allies were readying an invasion of Norway rather than of France (20/24 April 1944).

'Onion I' of 20 April was designed to suggest that Major General E. Hakewill-Smith’s British 52^nd Division was undertaking an amphibious landing exercise with the vessels of the fictional naval Force 'V', and 'Onion II' of 24 April to suggest that one brigade of the same division was making a training landing from the vessels of the same fictional naval force.