delusion

noun
1
a false belief or opinion about yourself or your situation
توهم, خیال باطل, باور نادرست, خیال واهی, پندار نادرست, گمان نادرست, گمان باطل
2
the act of believing or making yourself believe something that is not true
وهم, توهم, خیال باطل, پندار واهی, خیال خام, پندار غلط, خیال واهی
He seems to have retreated into a world of fear and delusion.
My mother had a tremendous capacity for delusion.
see also delude