Naming Vietnamese Lunar Years (Âm Lịch Việt Nam)

The year of the Rooster has just arrived. January 28, 2017 marked the beginning of a year that is full of progeress, honor and integrity. This is the year, which has been given the name Dậu  , as provided by the Vietnamese Lunar Calendar.

As naming the years is not as popular in other parts of the world, things for them might appear a little complicated to put together regarding how the years are named.

Whereas  the year 2014 was called Giáp Ngọ, the year 2015 was named Kỷ Mùi and the year 2016 was named Thân Khì the system of naming the years along with the cycles in the Lunar calendar would, in reality, only require a few basic understanding of this remarkably interesting calendar.

Naming a Vietnamese year is basically done by combining two cycles, the "Ten Heavenly Stems" and the "Twelve Earthly Branches".


Twelve Earthly Branches

The "Twelve Earthly Branches" ("shi er di zhi") denotes the twelve signs of the zodiac consisting of: (Rat), Sửu (Ox/Buffalo), Dần (Tiger), Mẹo/Mão (Cat/Rabbit), Thìn (Dragon), Tỵ (Snake), Ngọ (Horse), Mùi (Sheep/Goat), Thân (Monkey), Dậu (Chicken), Tuất (Dog) and the Hợi (Pig/Boar).


Ten Heavenly Stems

Meanwhile, the "Ten Heavenly Stems" ("shi tian gan" ...), comprised of Giáp, Ất, Bính, Đinh, Mậu, Kỷ, Canh, Tân, Nhâm and Quý are further associated with the concept of Yin and Yang as well as of with the five "Basic Elements" where Giáp and Ất belongs to "Wood", Bính and Đinh to "Fire", Mậu and Kỷ to "Earth", Canh and Tân to "Metal", and Nhâm and Quý to the element "Water". In relation to the two basic properties "yang" (Am) and "yin" (Duong), Giáp, Bính, Mậu, Canh and Nhâm are known to hold the qualities of "yang", while Ất, Đinh, Kỷ, Tân and Quý possess the "yin" qualities.


Naming the year

So putting two and two together, combining this year’s heavenly stem () in parallel with its property (yin) and Basic Element (Fire) to its earthly body rooster (Dao), 2017 Dậu Gá is labeled as "Yin Fire Rooster".

Combining in a round-robin manner the two shorter cycles of the "Can", or the ten-year cycle denoting the "Ten Heavenly Stems" and the "Gà" or the twelve-year cycle in congruent with the "Twelve Earthly Branches", a greater cycle of 60 years is formed. Derived from the least common multiple of 10 and 12, the 60-year cycle (called Can Chi) is more like how the centuries are divided into every 100 years.


The cycle

As it cycles continuously, a particular year will return every after 60-year period. Each year in the Can Chi corresponds to a particular year name.


Used in China since the second millennium B.C. as its manner of naming their days (pretty much how the Western world names the days of their week). The method utilizing the Sexagenary (Stem-Branches) cycle is evident throughout the Zhou dynasty as their records were found to be written in such manner. Its popularity is seen much widely around 202 BC-8 A.D. during the period of Western Han Dynasty. How and when it was adopted by several other East Asian countries (Japan, Korea, Vietnam...) varied throughout history.

Since a particular year returns after every Can Chi or passing sexagenary cycle, a year that began in 2000 will therefore enter a new cycle by year 2060. In the same manner, the previous Dậu  took place in 1957 which is exactly 60 years from today. When this cycle ends, the next Dậu , then, won’t be around until year 2077.