Collocations for illusion - noun

dangerous
To believe you have nothing more to learn is a dangerous illusion.

optical, visual
The road ahead looks wet, but in fact this is an optical illusion.

false
I don't want to give him any false illusions.

comforting
The slogan provides the comforting illusion that something is being done.

grand
I never had any grand illusions of winning.

romantic
I abandoned my romantic illusions a long time ago.

mere, pure, simple
The figure was only a trick of light, a mere illusion.

be under, entertain, have
They are under no illusions about the difficulties ahead of them.

create, give (sb), produce, provide
The huge size of the vehicle gives the illusion of safety.

foster, harbour/harbor, maintain, perpetuate, preserve, sustain
They are trying to maintain the illusion that the company is in good shape.

break, destroy, dispel, shatter
Within the first week at college all my illusions were shattered.

lose
I think I have lost all the illusions I had left.

illusion about, illusion as to
She had no illusions about her attractiveness.

be all an illusion
It turned out that their happy marriage was all an illusion.