Question: What is a verb for *illusion*? I want to use it in a sentence like the following:

> 
> The optical effect [illudes] my perception of its real shape.
> 
> 
> 

But **illude** does not exist. But I cannot find *illude* in my Dictionary (OS X Dictionary.app). I want to find a verb that is somewhere between *deceive* and *confuse*.

Answer: 
I think *[confounds](http://dictionary.reference.com/browse/confound?s=t)* is often used in this context.

> 
> The optical effect **confounds** my perception of its real shape.
> 
> 
> 

It has a nice feel of causing consternation without deceitfulness or the sort of blundery feel you get from "confuse." And whereas people tend to be confused, senses are confounded in [literature](http://www.google.com/search?q=confound+the+senses&btnG=Search+Books&tbm=bks&tbo=1).
I might use the word *obscures* in that sentence:

> 
> The optical effect obscures my perception of its real shape.
> 
> 
> 

From [Oxford Dictionaries](http://oxforddictionaries.com/definition/english/obscure): "obscure (verb): Keep from being seen; conceal".