As the sibling comment says, I think you somehow missed the -iard words. Since the words larger than thousand that are used most often (at this time) are milli

As the sibling comment says, I think you somehow missed the -iard words. Since the words larger than thousand that are used most often (at this time) are million and milliard/billion, I like the way milliard is very different from million and at the same time, in French, follows a kind of natural progression from mille, million, milliard.