[ReignOfError]

American football is nicknamed gridiron? By whom?

Folks who aren't American. Turns out, the name "football" was already taken.

[SoCal Pubbie]

You guys know darn well that the term “gridiron” in the U.S. refers to football, albeit rarely used used as a substitute noun itself. Rather, it is often used as a substitute adjective.

For example, NFL Films' production of "Gridiron Glory", and the recent film "The Gridiron Gang."

Now, can anyone tell me WHY the word "gridiron" refers to the game of American football?