Calendar terminology: a bilingual reference

Calendar and month terms

The Chinese calendar combines months governed by the Moon with a year kept in step with the Sun. Lunisolar describes that structure. “Lunar calendar” remains a familiar everyday name, but it does not express the solar part of the system.

The tables give Mandarin pinyin with tone marks. Chinese characters distinguish words that look similar in romanization.

Names for calendars

Pinyin	Chinese	English meaning and use
Nónglì	农历	Agricultural calendar: a common name for the traditional Chinese lunisolar calendar.
Yīnlì	阴历	Lunar calendar. Also used loosely for Nónglì, although the Chinese calendar is lunisolar.
Yánglì	阳历	Solar calendar: a structural category that includes the Gregorian calendar.
Gōnglì	公历	Gregorian calendar: the calendar used for present-day civil dates.
Yīnyánglì	阴阳历	Lunisolar calendar: the technical category combining lunar months with a solar-year framework.

Months, days and Moon phases

The phase definitions use ecliptic longitude, a position measured along the Sun’s apparent annual path across the sky. Geocentric means viewed from Earth’s center.

Pinyin	Chinese	English meaning and use
Rùnyuè	闰月	Leap month: an inserted lunar month that repeats the preceding month’s number. It is a whole month, not an extra day.
Shuò	朔	New moon: the conjunction when the Moon and Sun have the same apparent geocentric ecliptic longitude. The word also names the first day of a lunar month.
Wàng	望	Full moon: the phase when those longitudes differ by 180°. In traditional date wording, the word also names lunar day 15, although the astronomical full moon need not fall on that day.
Dàyuè / xiǎoyuè	大月 / 小月	Long month / short month: 30 lunar days / 29 lunar days. Together, dàxiǎo yuè means long and short months.

Lunar day and month boundaries

In the modern Chinese calendar, days run from midnight to midnight in UTC+8. A lunar month begins at midnight on the day containing the new moon, even when the conjunction occurs late that evening. The month’s start does not depend on sighting the first crescent. A lunar day is a numbered calendar day, rather than a fixed increment of the Moon’s phase.

Leap-month numbering

Under the modern rules, month 11 contains the winter solstice. When the interval from the start of one winter-solstice month to the start of the next contains 13 lunar months, the first month in that interval without a principal term is the leap month. It repeats the previous month’s number. A month without a principal term is therefore a leap-month candidate only within such a 13-month interval.

In 2025, regular month 6 was followed by leap month 6 before the numbering advanced to month 7.

Gregorian date	Lunar date	Meaning
25 June 2025	Month 6, day 1	Start of regular month 6, a 30-day month.
25 July 2025	Leap month 6, day 1	Start of the repeated month 6, a 29-day month.
23 August 2025	Month 7, day 1	Ordinary numbering resumes with month 7.

“Leap month 6” identifies a different month from regular month 6. The leap-month label is part of a complete lunar date, including a birth date or a date in a historical document.

Solar and cyclical terms

Solar terms mark positions in the seasonal year. The stem-and-branch cycle supplies repeating time labels. These systems can appear side by side without measuring the same thing.

Pinyin	Chinese	English meaning and use
Jiéqì	节气	Solar terms: usually the full set of 24, spaced at 15° intervals of the Sun’s ecliptic longitude. In a narrower contrast with zhōngqì, it can identify the alternating set of 12 non-principal terms.
Zhōngqì	中气	Principal terms: the alternating 12 terms at solar longitudes divisible by 30°. Also translated as “major solar terms.”
Tiāngān	天干	Heavenly stems: the set of 10 labels from Jiǎ to Guǐ.
Dìzhī	地支	Earthly branches: the set of 12 labels from Zǐ to Hài.
Gānzhī	干支	Ganzhi: the stem-and-branch cycle, or a combined stem-and-branch label within it.
Jiǎzǐ	甲子	The first stem-and-branch pair. The name also stands for a complete 60-part cycle.
Shēngxiào	生肖	The 12 zodiac animals associated with the earthly branches, such as Rat with Zǐ and Horse with Wǔ.
Hòu	候	A seasonal marker or short seasonal period. In the 72-pentad system, three such markers belong to each solar term.

The spring equinox is a principal term at 0°, Qingming is the next solar term at 15°, and Grain Rain follows at 30° as the next principal term. Principal and non-principal terms alternate throughout the cycle.

In Ganzhi, the two series advance together: Jiǎzǐ → Yǐchǒu → Bǐngyín. They return to their starting combination after 60 positions. “Sexagenary” simply means based on 60. A Ganzhi label can identify a year, month, day or traditional double hour, so the surrounding label is part of its meaning.

Almanac terms

An almanac is a publication containing calendar information and additional guidance. Its activity classifications and divinatory systems are separate from the astronomical rules that determine a lunar date.

Pinyin or established label	Chinese	Meaning in an almanac
Huánglì	黄历; also 皇历	A traditional almanac containing calendar dates, seasonal information and daily activity classifications.
Tōngshū / Tōngshèng	通书; 通胜	Names for almanac publications. Tung Shing is an established Cantonese rendering of 通胜, whereas Tōngshèng is Mandarin pinyin.
Yi — yí	宜	Suitable activities: the activities a particular entry recommends or permits within its traditional classification.
Ji — jì	忌	Activities to avoid: the activities that entry discourages.
Péngzǔ bǎijì	彭祖百忌	Pengzu taboos: traditional sayings attributed to Pengzu that associate particular days with activities to avoid.
Jiànchú	建除	The twelve day-officer sequence, named after its first two labels, Jiàn and Chú. Its assignment depends on the day’s branch and the month’s governing branch.
Chōng	冲	A clash or opposition relationship. In branch comparisons, the opposing labels lie six positions apart in the 12-branch cycle, such as Zǐ and Wǔ.
Shà	煞	An adverse influence in traditional almanac terminology. In a directional field, it identifies an unfavorable direction within that system. The word also occurs in the names of other adverse calendrical influences.
Nàyīn	纳音	A classification of stem-and-branch pairs within the five-phase system of wood, fire, earth, metal and water. It is distinct from the phase assigned to a heavenly stem alone.

Characters are especially useful when a page omits tone marks: yí 宜, “suitable,” differs from the stem Yǐ 乙; jì 忌, “avoid,” differs from the stem Jǐ 己. Likewise, an almanac’s kāi 开 day-officer label and the activity kāishì 开市, “open for business,” occupy different fields. One names a classification, the other an activity.