A decree of the emperor, fixing land tax valuation (Roman hist)
The tax itself (Roman hist)
A recurring period of fifteen years, instituted by Constantine the Great for fiscal purposes, and adopted by the popes as part of their chronological system
A year bearing a number showing its place in a fifteen years' cycle, reckoning from 24 September (or other day), 312AD (Roman hist)
ORIGIN: L indictiō, -ōnis, from indīcere to appoint