Hopper you are correct, I should have spelt it with a single L. And no, I dont understand how they could dream up a term like that, but they do seem to be happy its well and truly put to bed.
Probably the same basic (Latin/Greek) derivation as the metric prefix milli meaning 1/thousandth. They also use the word cent (derived presumably in the same way) and meaning one hundredth as the smallest unit of the dollar.