Separate but zep ah rah tay.

I taught some mathematical algorithm today. I wrote the steps out in words in one column, and an example in the another.

A student was reading, and copying silently, as all others were doing, when she belted with authority, "What the hell is (I'll write it phonetically) zep ah rah tay?"

I told her that the word was separate.

She said, "That's not how you spell separate."

Well, apparently not.