If veil refers to a covering for the face:
* Reveal
* Uncover
* Expose
* Disclose
If veil refers to something that hides or conceals:
* Reveal
* Unmask
* Expose
* Clarify
* Illuminate
If veil refers to a thin curtain:
* Open
* Expose
* Uncover
* Transparent
Ultimately, the best antonym depends on the specific meaning of "veil" in your sentence.