The Latin term indicates a kind of tunic that doesn't cover the arms, to the miles it was a garment brought under the armor for protect the tunic and the body from the rubbing and the dirt produced by the lorica, above all for the oils and fats used to preserve the metal from the corrosion (available in the Italian Section). This page instead contains the changes and the innovations (towards the original) that will be introduced from time to time. The original and full version is available here.