Pasidia gens
The gens Pasidia was an obscure plebeian family at ancient Rome. No members of this gens achieved any of the higher offices of the Roman state, but several are known from inscriptions. Origin. "Pasidius" appears to belong to a class of gentilicia derived from other names, chiefly cognomina, using the suffix "-idius". Morphologically, this implies that the name was formed from another name or word ending in "-idus", but as with other gentile-forming suffixes, "-idius" became stereotyped, and was sometimes used in cases when there was no morphological justification for it. There is no trace of a  cognomen "Pasidus", so the original root of the nomen is unclear, unless it is treated as an orthographic variant of "Pacidius", in which case the root may be the Oscan praenomen "Paccius". In any case, "Pasidius" seems to be the source for another nomen, "Pasidienus", derived from "Pasidius" using the gentile-forming suffix "-enus", not normally found in names of Latin origin, but typical of names from Picenum and Umbria.