In the Chinese zodiac, the 60-year cycle is called what?

In the Chinese zodiac, the 60-year cycle is called the sexagenary cycle.

The name refers to a traditional Chinese timekeeping system formed by combining 10 Heavenly Stems with 12 Earthly Branches. Because the two sequences realign after their least common multiple—60—the paired designations repeat every six decades. The system is also called ganzhi, meaning “stems and branches.”

The cycle was used to record days in China’s earliest written records, including Shang-dynasty oracle-bone inscriptions. Its use for naming years became widespread during the Han dynasty. The 12 zodiac animals belong to the Earthly Branches, while the Heavenly Stems add alternating yin-yang qualities and the traditional five elements.

A common mix-up is calling this merely the “Chinese zodiac cycle.” That usually means the 12-year animal sequence, whereas the sexagenary cycle is the larger 60-combination system. The 60th pairing returns to the first pairing, beginning a new round.