Southwestern Tai languages in the context of "Northern Thai language"

Thai, or Central Thai (historically Siamese; Thai: ภาษาไทย), is a Tai language of the Kra–Dai language family spoken by the Central Thai, Mon, Lao Wiang, and Phuan people in Central Thailand and the vast majority of Thai Chinese enclaves throughout the country. It is the sole official language of Thailand.

Thai is the most spoken of over 60 languages of Thailand by both number of native and overall speakers. Over half of its vocabulary is derived from or borrowed from Pali, Sanskrit, Mon and Old Khmer. It is a tonal and analytic language. Thai has a complex orthography and system of relational markers. Spoken Thai, depending on standard sociolinguistic factors such as age, gender, class, spatial proximity, and the urban/rural divide, is partly mutually intelligible with Lao, Isan, and some fellow Thai topolects. These languages are written with slightly different scripts, but are linguistically similar and effectively form a dialect continuum.

The Zhuang languages (/ˈdʒwæŋ, ˈdʒwɒŋ/; autonym: Vahcuengh, Zhuang pronunciation: [βa˧ɕuːŋ˧], pre-1982: Vaƅcueŋƅ, Sawndip: 話僮, from vah, 'language' and Cuengh, 'Zhuang'; simplified Chinese: 壮语; traditional Chinese: 壯語; pinyin: Zhuàngyǔ) are the more than a dozen Tai languages spoken by the Zhuang people of Southern China in the province of Guangxi and adjacent parts of Yunnan and Guangdong. The Zhuang languages do not form a monophyletic linguistic unit, as northern and southern Zhuang languages are more closely related to other Tai languages than to each other. Northern Zhuang languages form a dialect continuum with Northern Tai varieties across the provincial border in Guizhou, which are designated as Bouyei, whereas Southern Zhuang languages form another dialect continuum with Central Tai varieties such as Nung, Tay and Caolan in Vietnam. Standard Zhuang is based on the Northern Zhuang dialect of Wuming.

The Tai languages are believed to have been originally spoken in what is now southern China, with speakers of the Southwestern Tai languages (which include Thai, Lao and Shan) having emigrated in the face of Chinese expansion.Noting that both the Zhuang and Thai peoples have the same exonym for the Vietnamese, kɛɛu, from the Chinese commandery of Jiaozhi in northern Vietnam, Jerold A. Edmondson posited that the split between Zhuang and the Southwestern Tai languages happened no earlier than the founding of Jiaozhi in 112 BC. He also argues that the departure of the Thai from southern China must predate the 5th century AD, when the Tai who remained in China began to take family names.

Lao (ພາສາລາວ, [pʰáː.sǎː láːw]), sometimes referred to as Laotian, is the official language of Laos and a significant language in the Isan region of northeastern Thailand, where it is usually referred to as the Isan language. Spoken by over 3 million people in Laos and 3.7 million in all countries, it serves as a vital link in the cultural and social fabric of these areas. It is written in the Lao script, an abugida that evolved from ancient Tai scripts.

Lao is a tonal language, where the pitch or tone of a word can alter its meaning, and is analytic, forming sentences through the combination of individual words without inflection. These features, common in Kra-Dai languages, also bear similarities to Sino-Tibetan languages like Chinese or Austroasiatic languages like Vietnamese. Lao's mutual intelligibility with Thai and Isan, fellow Southwestern Tai languages, allows for effective intercommunication among their speakers, despite differences in script and regional variations.

Southern Thai (ภาษาไทยถิ่นใต้ [pʰaːsǎː tʰaj tʰìn tâːj]), also known as Dambro (ภาษาตามโพร [pʰaːsǎː taːm pʰroː]), Pak Tai (ภาษาปักษ์ใต้ [pʰaːsǎː pàk tâːj]), or "Southern language" (ภาษาใต้ [pʰaːsǎː tâːj]), is a Southwestern Tai ethnolinguistic identity and language spoken in southern Thailand, as well as by small communities in the northernmost states of Malaysia. It is spoken by roughly five million people and as a second language by the 1.5 million speakers of Pattani and other ethnic groups such as the local Peranakan communities, Negritos and other tribal groups. Most speakers are also fluent in or understand the Central Thai dialects.

The Zhuang languages (/ˈdʒwæŋ, ˈdʒwɒŋ/; autonym: Vahcuengh [βa˧ɕuːŋ˧], Sawndip: 話僮) are more than a dozen Tai languages spoken by the Zhuang people of Southern China in the province of Guangxi and adjacent parts of Yunnan and Guangdong. The Zhuang languages do not form a monophyletic linguistic unit, as northern and southern Zhuang languages are more closely related to other Tai languages than to each other. Northern Zhuang languages form a dialect continuum with Northern Tai varieties across the provincial border in Guizhou, which are designated as Bouyei, whereas Southern Zhuang languages form another dialect continuum with Central Tai varieties such as Nung, Tay and Caolan in Vietnam. Standard Zhuang is based on the Northern Zhuang dialect of Wuming.

The Tai languages are believed to have been originally spoken in what is now southern China, with speakers of the Southwestern Tai languages, which include Thai (modern-day Thailand), Lao (modern-day Laos) and Shan (modern-day Shan State, Myanmar) having emigrated south in the face of Chinese expansion. Noting that both the Zhuang and Thai peoples have the same exonym for the Vietnamese, kɛɛu, from the Chinese commandery of Jiaozhi in northern Vietnam, Jerold A. Edmondson posited that the split between Zhuang and the Southwestern Tai languages happened no earlier than the founding of Jiaozhi in 112 BC. He also argues that the departure of the Thai from southern China must predate the 5th century AD, when the Tai who remained in China began to take family names.

Thailand is home to 51 living indigenous languages and 24 living non-indigenous languages, with the majority of people speaking languages of the Southwestern Tai family, and the national language being Central Thai. Lao is spoken along the borders with the Lao PDR, Karen languages are spoken along the border with Myanmar, Khmer is spoken near Cambodia and Malay is spoken in the south near Malaysia. Sixty-two 'domestic' languages are officially recognized, and international languages spoken in Thailand, primarily by international workers, expatriates and business people, include Burmese, Karen, English, Chinese, Japanese, and Vietnamese, among others.

Isan or Northeastern Thai (autonym: ภาษาลาว/ພາສາລາວ, IPA: [pʰâː.sǎː lâːw]; Thai: ภาษาอีสาน, RTGS: Phasa Isan) refers to the local development of the Lao language in Thailand, after the political split of the Lao-speaking world at the Mekong River at the conclusion of the Franco-Siamese crisis of 1893. The language is still referred to as Lao by native speakers.

As a variety of the Lao language, Isan belongs to the Southwestern branch of Tai languages in the Kra-Dai language family. It is most closely related to (other than Lao) "tribal" Tai languages such as Phu Thai and Tai Yo. Isan is officially classified as a dialect of the Thai language by the Thai government. Although (Central) Thai is a closely related Southwestern Tai language, it falls within a different subbranch. Central Thai and Isan are mutually intelligible only with difficulty; even though they share over 80% cognate vocabulary, they have very different tonal patterns and vowel qualities, and many commonly used words in Isan differ from Thai, thus hampering comprehension.

Thái people (Vietnamese: người Thái) in Vietnam, also known as Táy people, are officially recognized by the Vietnamese government as one of Vietnam's 54 ethnic groups. They are Tai ethnic groups that speak various Tai languages and use the Tai Viet script. They mostly live in the Northwest Region of Vietnam and are culturally and linguistically distinguished from other Tai peoples of Vietnam such as the Nùng and Tày people, who are natives in the Northeast Region. In Vietnam, the Thái nomenclature is composed of several Tai groups, of which the main groups are the Black Tai (Tai Dam, Thái Đen), White Tai (Tai Don, Thái Trắng) and the Red Tai (Tai Daeng, Thái Đỏ). The Tai Lue people are officially classified as a separated group, called Lự. They mostly speak languages in the Chiang Saen branch of the Southwestern Tai languages. Thái people in Vietnam all originate from Yunnan. However, they (Tái minorities in Vietnam) are also different from the Thai people of Thailand although they are both related and speak Kra–Dai languages.