illusion
il|lu|sion /ɪl'uːʒən/ (illusions)
1 [N-VAR] oft N that, N of n/-ing
An illusion is a false idea or belief.
No one really has any illusions about winning the war.
= delusion
2 [N-COUNT] oft N of n/-ing
An illusion is something that appears to exist or be a particular thing but does not actually exist or is in reality something else.
Floor-to-ceiling windows can give the illusion of extra height...op|ti|cal il|lu|sion (optical illusions)
[N-COUNT]
An optical illusion is something that tricks your eyes so that what you think you see is different from what is really there.
Sloping walls on the bulk of the building create an optical illusion.
1 [N-VAR] oft N that, N of n/-ing
An illusion is a false idea or belief.
No one really has any illusions about winning the war.
= delusion
2 [N-COUNT] oft N of n/-ing
An illusion is something that appears to exist or be a particular thing but does not actually exist or is in reality something else.
Floor-to-ceiling windows can give the illusion of extra height...op|ti|cal il|lu|sion (optical illusions)
[N-COUNT]
An optical illusion is something that tricks your eyes so that what you think you see is different from what is really there.
Sloping walls on the bulk of the building create an optical illusion.