Thai names are comparable to the Western European pattern in which the family name follows a first or given name. In this, they differ from the family-name-first pattern of the general East Asian tradition.
Thai names (given and family) are often long, and there are a great many of them. The diversity of family names is because they are required to be unique to a family, and they are a recent introduction. Also, a number of Thai people change their given names relatively frequently (and their family names less frequently, as it requires permission of the head of a family or, in the case of children, father and mother). This practice is virtually unknown in most other countries outside of marriage and fortune-telling traditions. Besides standard reasons of separation and divorce, many name changes are done to get rid of bad luck (which, if caused by a ghost or spirit, would confuse the malignant entity, allowing the victim to get free from them).
Last names became legally required of Thai citizens in 1913.  Before then, most Thais used only a first or individual name. The names generally convey positive attributes. Under Thai law, only one family can use any given surname: Thus, any two people of the same surname must be related.[ citation needed]
Thai surnames are often long, particularly among Thais of Chinese descent. For example, the family of former Prime Minister Thaksin Shinawatra, who is of Chinese descent, adopted the name Shinawatra ("does good routinely") in 1938. According to the current law, Person Name Act, BE 2505 (1962), to create a new Thai surname, it must not be longer than ten Thai letters, excluding vowel symbols and diacritics.  The same law also forbids the creation of a surname that duplicated any existing surnames, There are some duplicates dating to the time before computer databases were available to prevent this.  Some creations added the name of their location ( muban, tambon or amphoe) into surnames, similar to family name suffixes.   
As a measure of the diversity of Thai names, in a sample of 45,665 names, 81% of family names were unique, and 35% of given names were unique: The people with shared family names are related, and the diversity of given names is conventional.[ dead link] 
East Asian monarchs often adopted regnal names upon ascending the throne, as was done in Thailand until the present day. In addition, subjects of a monarch may be awarded both a title and a name, such as in the case of Sing (or Singh) Sinhaseni (สิงห์ สิงหเสนี) who was awarded the title of Chao Phraya and the name of Bodindecha ( Thai: เจ้าพระยาบดินทรเดชา.)
Kings Rama I and Rama II were awarded noble titles and names before they assumed regnal names, which were then changed by subsequent kings. As neither noble titles nor names are necessarily unique, it is customary to list the highest title and awarded named first, followed by former names and titles (and personal and family names in parentheses) as needed.
Descendants of the nobility, both hereditary and non-hereditary positions, generally take the noble name of their ancestor for a surname. For instance, Hugo Chakrabongse is a descendant of Prince Chakrabongse Bhuvanath. Some (far removed) descendants of royalty add the preposition and nobility particle "na" ( ณ) to geographical names to create surnames, in the same way that members of German noble families use von.
Thus Mongkol Na Songkhla, a minister in the Surayud government, has a name indicating that he is a distant descendant of royalty or nobility in that geographical region (for instance, the surname "Na Chiangmai", belonging to descendants of the rulers of Chiang Mai, which was a vassal state of Siam). The name of Kasem Sanitwong Na Ayutthaya, another minister, indicates that he is related to the royal family, as it is also tradition for far-removed descendants to add " Na Ayutthaya" after their surnames. In this case, Sanitwong is the family name of Kasem. Sanitwong itself being a name of a royal consort of Rama V and the subsequent family name for her descendants.
The Council of Royal Pandits, predecessor to the Royal Institute of Thailand, was available to assist in deriving palace names, as they were called. For an example, see the background of the Vejjajiva palace name. The latter-day Royal Thai General System of Transcription would transcribe it as "Wetchachiwa". Formal personal names follow from traditional practice to include individual awards of palace-given names.
In polite speech, Thais address each or refer to each other by a given name, preceded by the courtesy title khun, particularly with persons of higher status or public distinction. Thus, the ministers mentioned above would be addressed and referred to as "Khun Mongkol" and "Khun Kasem". "Khun" pronounced with an even tone should not be confused with rising-tone khun, an obsolete feudal title, or ever replaced with " Khunying", comparable to formal Lady in Western culture, still sometimes awarded.
Informal names are awarded at birth and may continue in use to the extent one may have to check the formal registration to find a person's given formal name. Thais may address each other by nicknames ( Thai: ชื่อเล่น, translit. chue-len). Bestowed by relatives or playmates in early childhood, these are commonly one syllable (or worn down from two to one). These may often be nonsense words or humorous and seldom relate to the registered name except in cases where it is a diminutive, such as "Nok" for "Noknoi," or bird from little bird. All Thais have such names; they are freely used in everyday life. Some may have additional nicknames bestowed by friends or colleagues, especially during school or adolescence. Nicknames may link with a notable physical feature or behavior. In everyday life, a Thai is introduced by nickname and others may not know the person's formal name. When so introduced, one usually continues to use the nickname.
The evolution of Thai nicknames dates back to the Sukhothai era, when names were used to mark the order of children. Nicknames such as "Ai", "Yee", and "Sam" designated children as "one", "two", and "three". Later, in the Ayutthaya and Rattanakosin periods, children began to be named for physical attributes, such as "Daeng" (red) or "Uan" (fat) or for desirable items such as "Thong" (gold). Conversely, unflattering nicknames such as "Mah (dog)", "Moo (pig)", or "Kob (frog)" were employed to keep malign spirits from coveting the child. King Mongkut (Rama IV) (1804-1868) stimulated interest in naming babies in accordance with astrological principles as outlined in the ancient scripture, Namtaksapakorn. 
During the time of Field Marshal Plaek Phibunsongkhram (1897-1964), gender-based naming was introduced. Names ending in "-sak", "-chai", and "-yot" were for male babies, "-porn" or "-sri" for females. In the 21st century, assigning nicknames still relies heavily on astrological beliefs but in keeping up with current naming fashions. Observers have noted such modern nicknames as "Porsche", "Mercedes", "Benz", "Man U", "Big Mac", "Internet", and "Google", among others. 
King Bhumibol Adulyadej's nickname, for example, was Ong Lek ( Thai: องค์เล็ก; Ong is a numerative noun for kings, princes, princesses, priests, images of Buddha, gods, angels, palaces, pagodas; "lek" means "little (one)", a common name for younger siblings).  Former Prime Minister Thaksin Shinawatra's nickname is Thai: แม้ว, translit. Maew, Thai for the Miao people. By way of example preceding formal naming, Plaek Pibulsongkram's childhood name meant "strange". He later adopted as a surname what was originally an award for academic excellence and generally known in public life by the shortened form "Pibun." Thailand's first female Prime Minister, Yingluck Shinawatra, is nicknamed Pu "crab" (ปู; Thai pronunciation: [pūː ]). 
According to the Chicago Manual of Style, Thai names may be indexed depending upon the individual practice. Often they may be alphabetized under the given name with no comma and no inversion, but they may also be alphabetized under the surname with a comma and with an inversion. 
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ในจังหวัดนครราชสีมาหรือโคราชนั้น นิยมตั้งนามสกุลตามภูมิลำเนาที่เกิด หรืออยู่อาศัย ใช้ชื่อตำบล อำเภอ และหมู่บ้านเป็นส่วนท้ายของนามสกุล
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ชาวอำเภอโนนสูง ส่วนใหญ่ จะมีนามสกุล ลงท้ายด้วยคำว่า "กลาง" ซึ่งเป็นชื่อเดิมของอำเภอ เป็นส่วนใหญ่ ซึ่งเป็นเอกลักษณ์ของชาวอำเภอโนนสูง เช่นเดียวกับอำเภออื่น ๆ ในจังหวัดนครราชสีมา ที่นิยมลงท้ายนามสกุลด้วยชื่ออำเภอDOC(in Thai)
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