Thai Lunar Calendar

The Thai lunar calendar (, , , literally, ''Specific days according to lunar norms''), or Tai calendar, is a lunisolar Buddhist calendar. It is used for calculating lunar-regulated holy days. Based on the ''SuriyaYatra'', with likely influence from the traditional Hindu ''Surya Siddhanta'', it has its own unique structure that does not require the Surya Siddhanta to calculate. Lunisolar calendars combine lunar and solar calendars for a nominal year of 12 months. An extra day or an extra 30-day month is intercalated at irregular intervals.

Legal versus religious calendar

The Thai solar calendar (, , ), Thailand's version of the Gregorian calendar, replaced the ''patithin chanthrakhati'' in AD 1888 / 2431 BE for legal and commercial purposes. In both calendars, the four principal lunar phases determine Buddhist Uposathas, obligatory holy days for observant Buddhists. Significant days also include feast days.

Note that the Thai and the Chinese lunar calendars do not directly correspond. Thai Chinese likewise observe their Uposatha and traditional Chinese holidays according to solar terms, two of which correspond to one lunar phase. These also move with respect to the solar calendar, and so it is common for Thai calendars to incorporate both Thai and Chinese lunar calendar-based events.

Mundane astrology also figures prominently in Thai culture, so modern Thai birth certificates include lunar calendar dates and the appropriate Thai Zodiacal animal year-name for Thai Hora (, ). The Thai Zodiac is similar to the Chinese, though the Dragon is replaced by the Naga (งูใหญ่), and in Northern Thailand the Pig is occasionally replaced with an Elephant.

Years

To keep the years in sync with the seasons, Thai lunar years may add a day to the 7th month or repeat the 8th month. Therefore, years may have one of three lengths – 354, 355 or 384 days – yet retain a nominal length of twelve months.

*The 354-day-long years consist of 12 "normal months", and such a year is called a "normal-month year" (, , ).
*The 355-day-long years add an extra day to the normally 29-day-long 7th month; such a year is called an "extra-day year" (, , ).

*The 384-day-long years repeat the 30-day-long 8th month, thus keeping the month count at 12. Nevertheless, a year of 384 days is called an "extra-month year" (, , ).

New year

The Thai lunar calendar does not mark the beginning of a new year when it starts a new 1-to-12 count, which occurs most frequently in December.

The Thai solar calendar determines a person's legal age and the dates of secular holidays, including the civil new year and the three days of the traditional Thai New Year, which begin the next Twelve-year animal cycle. Should the holidays fall on a weekend, it also accommodates these as well as some of the principal lunar festivals with a compensatory day off (, ).

Twelve-year animal cycle

13 April of the solar calendar occasions the beginning of the traditional Thai New Year (Songkran) and is the day that a year assumes the name of the next animal in the twelve-year animal cycle; Thai Chinese communities may observe the name-change earlier in accordance with the Chinese New Year.

The Thai names of the months were borrowed from Khmer, which were in turn borrowed from Archaic Vietnamese.

Months

In the modern Thai calendar, months (, , , meaning "month" or "Lunation") are defined by lunar cycles. Successive months (or lunations) are numbered from 1 to 12 within the Thai year. As in other Buddhist calendars, these months have names that derive from Sanskrit, but for the most part are only known by Thai astrologers.

Two successive lunations take slightly more than 59 days. The Thai lunar calendar approximates this interval with "normal-month" pairs (, ) that are alternately 29 and 30 days long. 29-day " hollow months" (, , ) are odd-numbered (, , ); 30-day "full months" (, , ) are even-numbered (, , ).

To keep the beginning of the month in sync with the new moon, from time to time either the normally "hollow" Month 7 takes an extra day, or an extra "full" Month 8 follows a normal "full" Month 8.

Months 1 and 2 are named in archaic alternate numbers, with the remainder being named in modern numbers.

Months 1 – 6

Month 1, "duean ai" (, ), begins the cycle of counting the months anew, most frequently in December, but does not signify the beginning of a new year. ''Ai'', an archaic word in Thai but not in other dialects, means ''first''.On-line Royal Institute Dictionary
(ORID - 1999).
An odd-numbered hollow month, it is 29 days long.

Month 2, "duean yi", (, , from archaic ญี่ meaning ''2'') is an even-numbered full month.

Months 3–6, "duean 3–6", use the modern reading of Thai numerals, as do all remaining months. Months 3–6, alternate between 29-day hollow months and 30-day full months.

Month 7 and athikawan

Month 7, "duean 7", a hollow month is normally 29 days long in years of 354 days, but adds an extra day ( ) when required for 355-day-long years (, ).

Month 8

The eighth month, "duean 8", is a 30-day full month.

Month 8/8 "athikamat"

Athikamat (, )) is the extra month needed for a 384-day-long ''pi athikamat'' (extra-month year; , ). Month 8 repeats as เดือน ๘/๘ or Month 8/8, variously read as "duean paet thab paet" () or "duean paet lang" ()

Months 9 – 12

Months 9–12, "duean 9–12", complete the lunar cycle.

Month divisions

Months divide into two periods designated by whether they are waxing or waning:
*Waxing : ''khang khuen'' (), the period from new moon to full moon, is always 15 days long.
*Waning : ''khang raem'' (), the period from full moon to new moon, which is 14 days long in hollow months, except when Month 7 adds an extra day, and 15 days long in full months.

Weeks

A week is called ''Sapda/Sappada'' (, ). The term is defined by the Royal Institute Dictionary (RID) as a 7-day period beginning on Sunday and ending Saturday.RID on-line
When referring to lunations, however, it is the 7-, 8- or (rarely) 9-day interval between quartile lunar phases; that is, from one ''wan phra'' () to the next.

Days

While solar-calendar weekdays have names, lunar-calendar days number sequentially from 1 to 14 or 15 in two segments depending on whether the moon is waxing or waning. For example, "raem 15 kham duean 12 " means "Waning of the 15th Night of the 12th Lunar Month".

''Kham '', evening, is considered to be the evening of the common day that begins and ends at midnight, rather than of a day that begins and ends at dusk. Past practice may have been different.

Named lunar days

*''Wan Phra'' , Buddhist holy days
**''Wan Thamma Sawana'' Buddhist Uposatha regularly fall on:
***''Khuen 8'' first-quarter moon
***''Khuen 15'' full moon; also called ''wan phen'' day ffull oon However, ''Wan Deuan Phen'' , the actual day of the full moon and khuen 15 kham do not always fall on the same day.
***''Raem 8'' third-quarter moon
***''Raem 14 (15)'' the last day of the lunar month; also called ''wan dap'' day oon isquenched, r goesout.
*''Wan wai phra chan'' , called "Day fRespect orthe Holy Moon", is the actual day the Harvest moon becomes full. It occurs on ''khuen 14 (15) kham duean 10'' (Waxing 14 (15) Evening, Month 10.)

Holidays regulated by the moon

Uposatha, colloquially called , are the New, First-quarter, Full, and Third-quarter Moon-days. These are not normally days off (), except for butcher, barber, and beautician shops that observe the Eight Precepts. Annual holidays and seasonal festivals collectively are called .

Festivals or fairs are called ; these may be further styled as "traditional" and as , "rite" or "ceremony". The table shows the principal ones governed by the moon in yellow.

Work holidays prescribed by the government are called ; those regulated by the moon are red.

Weekends are normally days off; if a holiday normally observed by a day off falls on a weekend, the following Monday is a compensatory day off .

Notes:
: † The Chinese New Year uses different methods of determining intercalary months, so this festival sometimes occurs a month earlier or later.
: ‡ Month 8/8 in years with the extra month.

Thai year vocabulary

Thai orthography spells most native words phonetically, though there is no definitive system for
transcription into Roman letters. Here, native Thai words are immediately followed by a vocabulary entry in this pattern:
:''Phonetic'' Thai (Thai phonetic respelling, if different) ommentdefinition; variant definitions.
Example:
:''Thai'' ไทย (ไท) rchaicfree, frank; Thai race, language, alphabet; citizen of Thailand.

Sanskrit loan words follow different rules he way English grammatical rules vary for words of Greek and Latin origin ('ph-' in 'phonetic' being pronounced /f/, for example.)Entered below in order of first appearance, these vocabulary entries are in this pattern:
;''Sanskrit'' สันสกฤต (สันสะกฺริด /san-sa-krit/) :
Literally means "well done", "polished","cultured" or "perfected" in a modern usage (which implies the language of cultured persons); Sanskrit alphabet, language, writing; resumedcompound of
* ''san'' สัน (-/son/) derived from the prefix "saṃ" meaning "together, with, completely"
* ''skrit'' สกฤต (สะกฺริต /sa-krit/) derived from the root "kr" meaning "do or make".
; ''Chanthrakhati'' จันทรคติ (จันทฺระคะติ) : "Lunar norms", Lunar Calendar; compound of
* ''Chanthra-'' จันทร- (จันทฺระ) : ''Chan'' จันทร์ (จัน) moon, lunar +
* ''Kati'' คติ (คะติ) : ways, principles, norms
; ''Patithin'' ปฏิทิน (ปะติทิน) : Calendar; compound of
* ''Pati-'' ปฏิ- (ปะติ-) : anti-, re-, for, specific +
* ''-thin'' (-ทิน) : rom Sanskrit ''dina'': day.
* ''patithin'' means for days, specific days or fixed days
; ''Patitin Chanthakhati'' ปฏิทินจันทรคติ (ปะติทินจันทระคะติ) : "Specific days according to lunar norms", Lunar Calendar
; ''Suriyakhati'' สุริยคติ (สุริยะคะติ) : ''Solar norms'', Solar Calendar; compound of
* ''Suriya'' สุริย or สุริยะ : ''Athit'' อาทิตย์, the sun, Sol +
* ''Khati'' คติ (คะติ) : ways, principles, norms
; ''Prokkatimat'' ปรกติมาส (ปฺรกกะติมาด) : normal month; compound of
* ''Prokkati'' ปรกติ (ปฺรกกะติ) : ''pakati'' ปกติ (ปะกะติ) ordinary, usual, normal +
* ''Mat'' มาส (มาด) : ''duean'' (เดือน) month.
; ''Athikamat'' อธิกมาส (อะทิกะมาด) : month added in leap-month lunar years
; ''Athikawan'' อธิกวาร (อะทิกะวาน) : day added in leap-day lunar years; compound of
* ''Athika'' (Sanskrit: ''adhika'') : additional +
* ''-wan'' วาร (Sanskrit: ''vāra'') : ''wan'' วัน day.
;''Athikasurathin'' อธิกสุรทิน (อะทิกะสุระทิน) : day added to February in a solar leap year.

See also

* Public holidays in Thailand
* The Royal Institute of Thailand
* Thai solar calendar
* Thai 6-hour clock
* Time in Thailand
* Traditional Burmese calendar

References

Further reading

*
* Eade, J.C. ''The calendrical systems of mainland south-east Asia''. (Cited by Diller & Preecha)
* Sethaputra, So. ''New Model English - Thai Dictionary'',

External links

Thai Time by Anthony Diller
– last changed 10 January 2002.
* in Thailand: article for stamp collectors recovered 20 December 2007.

Thai Lunar Calendar (BE.2300-2584)
(Thai Language)

{{Thailand topics

Lunar calendar
Lunisolar calendars
Specific calendars
Calendars