Chinese cultural term · reviewed 2026-10-21
天干
Heavenly Stems
tiān gān · heavenly stems
A cycle of ten labels used with Earthly Branches to name positions in the traditional sexagenary calendar.
A familiar bridge
Start from something known.
A repeating set of ten counters whose combinations create a longer cycle, somewhat like a calendar modulo system.
Worked example
See the term in position.
The sequence begins Jia, Yi, Bing, Ding, Wu, Ji, Geng, Xin, Ren, and Gui.
Cultural context
What surrounds the word.
Each Four Pillars position pairs one Heavenly Stem with one Earthly Branch. Stems also carry polarity and Five Phase associations.
Boundary
What it does not mean.
A stem is not a chemical element or a standalone personality result; its role depends on the position and method.
Inside the portrait
How this term appears here.
The portrait records the calculated stem for each available pillar and reads the day stem as the Day Master position.