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Number of Speakers: 37 million

Key Dialects: See below

Geographical Center: Thailand

Thai, sometimes referred to as Siamese, is spoken in the central plains of Thailand and in Bangkok, the capital. Estimates of total numbers of speakers vary widely as well as the percentages of the total population of Thailand who speak Thai. Low estimates cite 20 to 25 million speakers, or about 45 percent of Thailand's population; high estimates are for about 37 million speakers or 80 percent of the population. This includes almost 5 million ethnic Chinese who are Thai speakers and almost 500,000 speakers of Khorat, a dialect of Thai. Small populations, less than 15,000 each, use the language in the USA, the United Arab Emirates, and Singapore.

Thai is a member of the Southwestern subgroup of the Tai or Dai family whose better known members include: Lao, or Laotian, spoken in the Mekong River valley of Laos by 3 million people; Shan with 2.5 million speakers in southeast Burma and smaller numbers in Thailand; and Southern Thai with 4.5 million speakers in Thailand's southern peninsula. Some scholars place the Tai family within the phylum of Austric languages whose other major subdivisions are: Miao-Yao, which is spoken in southern China, northern Vietnam, and northern Laos; Austroasiatic, which includes, for example, the Mon-Khmer languages; and Austronesian, which includes the Malayo-Polynesian languages (Ruhlen 1987:287). Other authorities are less clear about the external affiliations of the Tai family.

The dialect situation--that is, what is properly a variant of Standard Thai or a separate language--has not been settled. Some list only Khorat Thai as a dialect (Grimes 1992). Other distinctions are made between the dialect of Bangkok and that of Central Thai itself.

Others group Northern Thai (Lanna), Northeastern Thai (Isan), and Southern Thai as variants or regional dialects of Standard Thai (Ronnakiet 1994). Others are ambiguous about the question (Hudak 1987:759). Still other authorities list these as separate but closely related languages (Diller 1992). A terminological problem also exists: Isan, which is closely related to Lao and spoken in northeastern Thailand, is also called Northeastern Thai; Lanna which is spoken by the Khon Muang people in the northern provinces of Thailand is also called Northern Thai; Lao, which is spoken in Laos is also called Eastern Thai.

Thai uses a script that is basically alphabetic in nature with some elements of a syllabic system. In origin it derives from an Indic script which was adapted first by the Khmer and then the Thai. There is a fairly good approximation between the script and pronunciation.

Thai is a language which is devoid of inflection; some refer to this type of language as "isolating," that is a situation where grammatical relations are expressed by single words, or combinations of single word, by the use of independent particles, and by word order, rather than by affixes. Nouns are not marked for number, gender, or case, and verbs likewise are not inflected for person, number, tense, and other distinctions. There are limited, semiproductive, derivational processes whereby, for example, nouns might be derived from verbs; but compounding is extensive and productive.

In counting, Thai uses a system of classifiers where a classifier follows the noun and precedes the numeral. There are separate classifiers for objects that are ordinary human beings, for royalty, for monks and sacred objects, and others for hermits and giants, and so on. Often there is no easy determined semantic feature indicating what classifier goes with what noun; thus, animals, shirts, trousers, kites, chairs, etc. govern one classifier; there is another for cars, bicycles, plows, umbrellas, spoons, etc. and yet another for fruit, jars, pillows, hats, baskets, suitcases, etc. and so on.

Tense distinctions in verb phrases are either determined by context or by adverbs and expressions of time. Complex verbal predicates in serial configuration are used to convey expressions which in English would be stated by adverbs or auxiliary verbs to indicate mood.

Genitive relationships are expressed either by apposition with the noun juxtaposed with the possessor, or by use of a linking particle. In colloquial Thai word order is discourse sensitive and topic prominent, thus Object-Subject-Verb occurs and Subject-Object-Verb order is sometimes possible, but in Standard Thai Subject-Verb-Object word order is taught as the norm. Also in Standard Thai prepositions can be used but are often omitted depending on style and other variables.

Sociolinguistic variables play an important role in expression. For instance, Thai has a set of particles that come at the end of a sentence--which are used to make simple statements or ask yes-no questions--but there are also particles that indicate respect or deference towards the addressee or that convey the speaker's attitude about the narrated event or situation.

In the phonology there are nine vowel phonemes which can be short or long, and twenty consonant phonemes. A salient feature is the contrast between aspirated and unaspirated voiceless stops. It is a tonal language with lexical tone where words can be distinguished by five contrastive tones.

Thai has borrowed heavily from Mon and Khmer. Literary Thai depends on Sanskrit and Pali, another Indic language, for much of its learned vocabulary--a situation analogous to English's dependence on Latin. Chinese has also been an important source of an early loan set contributing numerals and some few hundred basic terms. In the modern era culinary and commercial vocabulary has also entered the language from Chinese. Because of the polysyllabic nature of the large amount of Indic loans, Thai changed from a basic monosyllabic language in its morphemic structure to one that is now polysyllabic. English has also become an important source of loans especially in the popular cultural sphere, in the mass media, and in commerce.

Thai is the official national language in Thailand and is used in education, the media, and government administration and bureaucracy. Most Thai people who are not native speakers--that is speakers of the many minority languages (e.g., other Tai languages, and languages belonging to Mon-Khmer, Malayo-Polynesian, and Tibeto-Burman groups)--have at least some passive competence in the language. Official policy is to promote and further Standard Thai in order to create unity among linguistic diversity. Thai itself, along with Chinese and English, is a functioning trade language.

The Thai regard their language as very complicated and difficult to learn. This reflects the prevalent diglossia in the country--whereby two nonregional varieties of Thai are used in complementary situations--which itself reflects extreme social stratification. Alongside the form of speech used by common people and the peasantry--the "low" form used in everyday mundane conversation--a "high" or royal form exists and is characterized by specialized vocabulary and stylistic devices. The high form is only used when talking about the king, queen, and other members of the royal family, high ranking Buddhist clergy, and some of the aristocracy. The "high" register is characterized by a vocabulary of Indic borrowings, specifically: Sanskrit, Pali, and to a lesser extent, Khmer. Some syntactic features of Thai are also part of the distinction. Prescriptivism plays an inordinate role in the ongoing standardization process that began in the nineteenth century.

Newspapers and periodicals are mainly in Standard Thai, but some are printed in Chinese, English, and Malay. Radio is mainly in Standard Thai but there are regional programs in other Tai languages, in Chinese, and in English.

The Thai, who originated in China, migrated into the Indochina peninsula before the current era. Initially dominated by the Mon and then later, beginning in the tenth century, by the Khmer, the Thai gained their own independence in the mid-thirteenth century. Shortly thereafter, the first script--known as the Sukhotai and distinct from that used by the Khmer--was developed for Thai. The script now in use is a more or less modified variant of this and other intervening scripts used during the reign of other monarchs.

From the twelfth to twentieth centuries, the country was know as Siam and the language as Siamese. In 1939 the country was officially designated as the Thai Kingdom. Thai is first attested by an inscription dated to the late thirteenth century. The oldest piece of literature is a Buddhist cosmography dating from the fourteenth century. There are Thai versions of the Ramayana, a Hindu epic, and other Hindu literature; these are recent recensions but based on ancient oral tradition. Similarly there are the Thai chronicles, known as the Phongsawadan and the Prachum Phongsawadan. A popular form of literature among poets of the seventeenth to nineteenth centuries, known as nirat, dealt with human kind as itinerant wanderers. In the current century the western novel has come into its own.

Campbell, G. L. 1991. Compendium of the World's Languages, Vol. 1 -2. London and New York: Routledge.

Diller, A. 1992. "Tai." In W. Bright, ed. International Encyclopedia of Linguistics, Vol. 4:128-131. New York and Oxford: Oxford University Press.

_____ 1992. "Thai." In W. Bright, ed. International Encyclopedia of Linguistics, Vol. 4:149-156. New York and Oxford: Oxford University Press.

Grimes, Barbara F., ed. 1992. Ethnologue, Languages of the World. Dallas, TX: Summer Institute of Linguistics.

Hudak, T. J. 1987. "Thai." In B. Comrie, ed. The World's Major Languages, pp. 757-775. New York: Oxford University Press.

_____. 1994. "Thai." In R. E. Asher, ed. The Encyclopedia of Language and Linguistics, Vol. 9:4600-4601. Oxford: Pergamon Press.

Linguistic Society of America. 1992. Directory of Programs in Linguistics in the United States and Canada. Washington, DC.

Ronnakiat, N. 1994. "Thai Writing System: History." In R. E. Asher, ed. The Encyclopedia of Language and Linguistics, Vol. 9:4601-4602. Oxford: Pergamon Press.

_____. 1994. "Thailand: Language Situation." In R. E. Asher, ed. The Encyclopedia of Language and Linguistics, Vol. 9:4602-4603. Oxford: Pergamon Press.

Ruhlen, M. 1987. A Guide to the World's Languages, Vol. 1: Classification. London: Edward Arnold.

Streker, D. 1987. "Tai Languages." In B. Comrie, ed. The World's Major Languages, pp. 747-756. New York: Oxford University Press.

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