If you say football, in most of the English speaking world it's ambiguous. For instance, in 1886 Hawick Football Club joined the Scottish Football Union and Hull Football Club (est 1865) still plays in Superleague XV.

In the 50's as children, while we played "football" to something like Association rules, we were well aware that there were different forms of the game. For modern Association football followers to claim excusive use of the term is just an arrogant denial of the game's variety and history.