When he was two years old, my nephew called it "Run, run, run, fall down". Actually, come to think of it, that's as good a name as any others suggested so far.
I was once, many years ago, dating a young lady who had only recently arrived in Canada, and had never seen a football game until meeting me.
Her description of it was, to the best of my recollection, "big fat men get into a circle, share a secret, then line up, and when the whistle blows, they all fall down."
Rugby is named after Rugby School, where the sport originated. Canadian football in its current form originated at the University of Toronto (the rules we use now are based largely on those of Thrift Burnside, captain of the U of T football team). Thus, if we followed the lead of Rugby, we would call Canadian football "Toronto". That would ensure the death of the sport, however, as Toronto hardly cares about the sport as it is, and no one outside of Toronto would want to play anything named after that city.
In developing those rules, Burnside was inspired by Walter Camp, a coach and player at Yale, who came up with the original rules of American football. Thus, again following the lead of Rugby, American football would be called Yale.