Mǎo

the hour the gate opens

Unicode: U+536F cjk unified ideograph-536f
Meaning: The fourth of the twelve earthly branches: the double-hour from five to seven, and the direction due east.
History: One member of a closed cycle of twelve used to count years, months, hours and directions at once — a single set of glyphs indexing four different quantities, which is what makes the branches a symbol system rather than a numbering.
Variants: The oracle-bone and seal forms differ; the modern graph is stable.
Related: 午 its opposite in time, 酉 its opposite in space; the full branch cycle. Read as a word in the Lexicon.
Appears: Almanacs, traditional calendars, hour and direction reckoning, and the zodiac animal cycle.
Evolution: Calendrical index → direction marker → a word for dawn treated as an act.

Sources · 3

documented The twelve earthly branches as a combined system of hours, directions, months and years.
documented Xu Shen, Shuowen Jiezi, on the graph.
traditional The reading of the graph as two opened door-leaves — the standard gloss, and a reconstruction.