[SoCal Pubbie]

The word gridiron IS used as substitute for football right here in America. If you google the word most of the entries refer to its usage as a term for American football, including the “Gridiron Gang” official site, a site about Indiana high school football and even a ESPN fantasy NFL game. Try going to
www.nike.com/nikegridiron and see if they have basketball shoes there.

[ReignOfError]

The word gridiron IS used as substitute for football right here in America.

But rarely as a noun. In the phrase "gridiron gang," it's an adjective. "Gridiron shoes," adjective. I have never heard someone say "hey, buddy, I've got beer chilling and chips and salsa, you wanna come over and watch some gridiron on TV?"

That's the US. I've never been to Australia, so for all I know it might be common to call up a friend and say "Eh, mate, I've got Foster's on ice and shrimps on the barbie, wanna watch some gridiron on the telly?"

(It helps if you imagine the last bit in a really bad imitation of a Crocodile Dundee accent)