This Ba Zi glossary defines every core term you will meet in a chart, in two or three plain sentences each, with no mysticism and no jargon left standing on its own. Ba Zi (八字 bāzì) has a compact vocabulary, and once these words are clear the whole system reads more easily. Where a term has a fuller page on the site, its name links there, so treat this Ba Zi glossary as a map: skim it, then follow any thread that interests you. If you want to see these terms in your own chart, the calculator plots it free, and the What is Ba Zi hub gives the wider picture.
The foundations
Ba Zi (八字 bāzì) — literally “eight characters.” The system that reads your birth moment as four pairs of characters, one pair each for year, month, day and hour, and interprets their elemental relationships. Also called the Four Pillars.
Four Pillars (四柱 sì zhù) — the four columns of the chart: year, month, day and hour. Each is a vertical pair of one stem over one branch, and each governs a phase of life and area of experience, from your roots to your later years and the hour pillar.
Heavenly Stem (天干 tiāngān) — the ten “trunk” characters that sit on top of each pillar. Each stem is one of the five elements in either its yang or yin form, and the stems are the most visible, active layer of the chart.
Earthly Branch (地支 dìzhī) — the twelve “branch” characters that sit beneath each stem, the same twelve associated with the zodiac animals. Branches carry the seasons and the hidden stems, and they interact through clashes, combinations and other relationships.
Hidden Stems (藏干 cánggān) — the stems concealed inside each earthly branch, usually one to three of them. They add depth the surface characters do not show, and a reader weighs them to understand a branch’s true elemental content.
Five Elements (五行 wǔxíng) — Wood, Fire, Earth, Metal and Water, the elemental cycle underlying everything in the chart. They generate and control one another in fixed relationships, and balancing them is the heart of interpretation.
Yin and Yang (阴阳 yīnyáng) — the two complementary polarities every stem and branch carries. Each of the five elements appears in a yang (active, expansive) and a yin (receptive, contained) form, giving ten stem types in all.
The self and its measures
Day Master (日主 rìzhǔ) — the stem on top of the day pillar, which represents you. Everything else in the chart is read in relation to it, and its element is your true “birth element.” See the ten Day Masters guide for all ten.
Strong or Weak (身强身弱 shēn qiáng shēn ruò) — a judgement of whether your Day Master is well supported or under-resourced within the chart. It is not “good” or “bad”; it simply guides which elements help and which strain you.
Ten Gods (十神 shíshén) — the ten roles other stems play relative to your Day Master, such as resource, output, wealth and authority. They translate raw elements into meaning about people, drives and circumstances.
Useful God (用神 yòngshén) — the element the chart most needs to come into balance, chosen after judging the Day Master’s strength. Identifying it well is the practitioner’s central skill and shapes most practical advice.
Time and the calendar
Li Chun (立春 lìchūn) — the solar term that begins spring and, in Ba Zi, marks the turn of the year. The year pillar changes at Li Chun, not at Chinese New Year, which is a frequent source of calculator errors.
Solar Terms (节气 jiéqì) — the twenty-four points that divide the solar year, tracking the sun’s position. Ba Zi months change at these terms, never at calendar or lunar month starts.
Luck Pillar (大运 dà yùn) — a ten-year cycle that overlays your natal chart, shifting the elemental climate you live through. Reading how each luck pillar interacts with your chart is where Ba Zi’s timing is strongest.
Annual Pillar (流年 liúnián) — the stem and branch of the current year, layered on top of your chart and luck pillar. It fine-tunes the timing, showing which themes a given year emphasises.
Ben Ming Nian (本命年 běnmìngnián) — your “year of origin,” the year whose zodiac animal matches your birth-year branch, returning roughly every twelve years. It is traditionally treated as a year to move with care, and each annual profile notes whose it is.
Relationships between branches
Clash (冲 chōng) — a direct opposition between two earthly branches that unsettles what they govern. Clashes are not automatically bad; they signal movement, friction or change that a reading interprets in context.
Combination (合 hé) — a bond between stems or branches that draws them together, sometimes transforming into another element. Combinations can stabilise a chart or lock up an element that was doing useful work.
Harm (害 hài) — a subtler adverse relationship between two branches, gentler than a clash but corrosive over time. It often shows up as quiet wear in the area of life those branches touch.
Punishment (刑 xíng) — a group of branch relationships associated with self-created friction, complications or internal tension. They are read carefully, since their effect depends heavily on the rest of the chart.
Three Harmony (三合 sān hé) — a trio of branches that together form a strong elemental frame, reinforcing one element powerfully. When present, it can dominate the chart’s elemental balance.
Symbolic stars and special points
Na Yin (纳音 nàyīn) — the “melodic element” assigned to each pair of pillars, a poetic layer with names like Sea Metal or Furnace Fire. It adds flavour and personality colour but sits secondary to the core elemental mechanics.
Shen Sha (神煞 shénshà) — the broad family of symbolic “stars,” auspicious and inauspicious points derived by formula from your pillars. They add nuance and imagery, though careful practitioners treat them as seasoning rather than structure.
Peach Blossom (桃花 táohuā) — a shen sha associated with charm, attraction and romantic magnetism. Its presence colours how relationships and social appeal show up in a chart.
Nobleman (贵人 guìrén) — a favourable shen sha marking help from others, mentors and timely support. It points to where and how outside assistance tends to arrive.
Void (空亡 kōngwáng) — branches that fall “empty” relative to the day pillar, said to weaken or hollow the matters they represent. Its handling varies between schools, and it is weighed alongside everything else, never alone.
Spouse Palace (夫妻宫 fūqī gōng) — the day branch, which represents your partner and marriage life. A reader looks here, and at the stems it interacts with, to understand the relationship area of the chart.
A related system
Zi Wei Dou Shu (紫微斗数 zǐwēi dǒushù) — a separate Chinese chart system, often abbreviated ZWDS, built from the lunar calendar and read through twelve palaces and over a hundred stars. It is complementary to Ba Zi rather than a rival, and many practitioners read both.
That is the working vocabulary. If a term made you curious about your own chart, the honest next steps are to read on where the links lead, to keep the limits of any symbolic system in mind as we set out in whether Ba Zi is accurate, and to see what a session actually involves in what happens in a Ba Zi reading. You might also compare traditions in Ba Zi versus Western astrology, or sort out your feng shui birth element, and explore your own stem through a profile such as Gui Water. When you are ready, plot your chart free with the calculator and find these terms in it.