Rugby is a collective name for the family of team sports of rugby union and rugby league, as well as the earlier forms of football from which both games, as well as Australian rules football and gridiron football, evolved.
The two variants of gridiron football Canadian football and, to a lesser extent, American football were once considered forms of rugby football but are seldom now referred to as such.
In fact, the governing body of Canadian football, Football Canada, was known as the Canadian Rugby Union as late as 1967, more than fifty years after the sport parted ways with the established rules of rugby union or league.