indiction

noun

1. a proclamation made every 15 years in the later Roman Empire, fixing the valuation of property to be used as a basis for taxation.
2. a tax based on such valuation.
3. Also called cycle of indiction. the recurring fiscal period of 15 years in the Roman Empire, long used for dating ordinary events.Compare lustrum.
4. a specified year in this period.
5. the number indicating it.

noun (in the Roman Empire and later in various medieval kingdoms)

1. a recurring fiscal period of 15 years, often used as a unit for dating events
2. a particular year in this period or the number assigned it
3. (from the reign of Constantine the Great)
   1. a valuation of property made every 15 years as a basis for taxation
   2. the tax based on this valuation