Today's clue from the New York Times crossword puzzle is : Concept that was called 36-Across before research into the square root of negatives First let's look and see if we can find any hints in the New York Times crossword puzzle. Then we will gather any relevent information we need in order to find the correct answer to the clue Concept that was called 36-Across before research into the square root of negatives that has been given in the New York Times crossword puzzle. Finally we will list any possible answers here below for the clue Concept that was called 36-Across before research into the square root of negatives.