Biblical; NT Gospels, esp. Mark ch.14. Herodias was the sister-in-law of Herod, King of Judea. We have not been able to find a meaning for either name.

A correspondent [LPC] reports the frequent use of Herodias in an extended family in Lincolnshire, England during the mid-Victorian period. The alternative spelling Herodius appears to be a single mis-spelling.