staggered is usually said when the wheels & tires are different widths front to rear, typically when someone says staggered wheels that is what is ment. different offsets could technically be called a staggered offset though because they are not lined up, technically staggered just means different front to rear, not in line with each other, but different offset are not what is really considered staggered wheels
staggering the offset like that shouldn't affect alignment or tirewear much if at all really...