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Astral Atlas
Wiki concept · Chinese & East Asian calendars

Wu stem

Also called Wu Heavenly Stem

Wu (戊) is the fifth Heavenly Stem, classified as Yang Earth.

In this entry

Two different labels written as Wu

The Wu stem is 戊, fifth in the stem series. The Wu branch is 午, seventh in the branch series. HKO’s cycle includes Wu-Wu: in that pair the first Wu names a stem and the second names a branch. Keep the characters and roles visible when comparing romanized labels.

Hong Kong Observatory · stem–branch sequence and hour tables ↗Joey Yap · Day Master and branch reference table, page 5 ↗

What Yang Earth identifies

Joey Yap’s reference table classifies 戊 as Yang Earth. This identifies the stem’s phase and polarity in the named framework. It does not make a Wu branch into an Earth stem, and it does not establish a psychological trait.

Joey Yap · Day Master and branch reference table, page 5 ↗

Read the position before its relationships

A Wu stem in the day pillar is the Day Master for that chart. In another pillar it is a stem to compare with the chart’s actual Day Master. The Ten Gods inspector derives that relationship from both stems, so the label Wu alone does not select a universal Ten Gods meaning.

In a saved report, keep the pillar position, complete pair and calculation settings alongside the reading. If changing a clock convention changes the day stem, inspect the resulting relationship labels again. An unchanged stem in one position does not guarantee that every derived relationship stays the same.

Word origin · etymology

Romanized Chinese calendrical name Wu (戊), ordinal 5.

Historical character derivation is not established by the cited calendar tables.

HKO: Stems and Branches ↗

How we know · epistemology

Calendrical convention

Stem phase and polarity are calendrical classifications, not traits.

Joey Yap: What Is BaZi Astrology? ↗

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Connected concepts

Read alongside this entry

These links connect subjects and terminology. They do not establish a shared historical origin.

Sources & provenance

Use the citations beside each section to distinguish a calculation convention, a historical teaching and an editorial example.

Find these sources across the wiki →

  1. Hong Kong Observatory · stem–branch sequence and hour tables ↗
  2. Joey Yap: What Is BaZi Astrology? ↗
  3. Joey Yap · Day Master and branch reference table, page 5 ↗