in Chronology, a certain period or series of numbers, which regularly proceed from the first to the last, and then return again to the first, and so circulate perpetually. See Chronology, No. 26.

CYCLE of Indiction, is a series of 15 years, returning constantly around, like the other cycles, and commenced from the third year before Christ; whence it happens, that if 3 be added to any given year of Christ, and the sum be divided by 15, what remains is the year of the indiction.

CYCLE of Indiction, a period of 15 years, in use among the Romans. It has no connection with the celestial motion, but was instituted, according to Baronius, by Constantine; who having reduced the time which the Romans were obliged to serve to 15 years, he was consequently obliged every 15 years to impose, or indicere according to the Latin expression, an extraordinary tax for the payment of those who were discharged; and hence arose this cycle, which, from the Latin word indicere, was styled indiction.

CYCLE of the Moon, called also the golden number, and the Metonic cycle, from its inventor Meton the Athenian, is a period of 19 years, which when they are completed, the new moons and full moons return on the same days of the month, so that on whatever days the new and full moons fall this year, 19 years hence they will happen on the very same days of the month, though not at the same hour, as Meton and the fathers of the primitive church thought; and therefore, at the time of the council of Nice, when the method of finding the time for observing the feast of Easter was established, the numbers of the lunar cycle were inserted in the kalendar, which, upon the account of their excellent use, were set in golden letters, and the year of the cycle called the golden number of that year.

CYCLE of the Sun, a revolution of 28 years, which being elapsed, the dominical or Sunday letters return to their former place, and proceed in the same order as before, according to the Julian kalendar.