perish the thought

perish the thought  {v. phr.}
Let us not even think of it; may it never come true. — Used as an exclamation.
If John fails the college entrance exam — perish the thought — he will go back to high school for one more year.
Perish the thought that Mary should have cancer.
Compare: GOD FORBID.
Categories: God exclamation {v. phr.}