Farang (in Thai: ฝรั่ง), sometimes pronounced falang, is the generic Thai word for a foreigner of European ancestry. While generally farang is a neutral word, it can be used in a mocking manner, or even as an insult depending on the context. For instance, the expression "farang ta nam khao" (in ฝรั่งตาน้ำข้าว - which literally means "farang with a rice-milk-colored iris") would be considered an insult. It is common in Thai to just say "farang" to point out the presence of one, without making a whole sentence. African Americans have been occasionally referred to as farang dum (black farang) in ฝรั่งดำ especially American servicemen during the Vietnam War.
Varieties of food/produce which were introduced by Europeans are often called 'farang' varieties. Hence, potatoes are man farang (in Thai: มันฝรั่ง), whereas man (มัน) alone can be any variety tuber; parsley is called phak chii farang (ผักชีฝรั่ง, literally farang cilantro); and chewing gum is maak farang (หมากฝรั่ง). Maak (หมาก) is Thai for betel, which many rural Thais chew for the euphoria it gives. When chewing gum was introduced, it was labeled maak farang, from association with a "chew".
In the Isan Lao dialect, the guava is called bak seeda (TH: บักสีดา "guava"), which is sometimes jocularly refers also to a farang.
Another common etymology, which explains why many other Southern Asian and Southeast Asian languages use the word, has to do with the French but in a more indirect way, saying that it derives from the earlier Persian word farangi, 'foreigners'. This in turn comes from the word Frank via the Arabic word firinjia, which was used refer to the Franks, a West Germanic tribe that became the biggest political power in Western Europe during the early Middle Ages and from which France derives it's name. France was later the first European nation that helped the Ghajar Kings modernize the Iranian government, in particular with the establishment of customs. Long before English, and until about the 1960s, French was the foreign language of choice for educated Iranians. The abundance of French words in the Persian language attests to this fact.
By another account the word comes through Arabic ("Afrandj"), and there are quite a few articles about this. One of the most detailed treatments of the subject is by Rashid al-din Fazl Allâh.
Farang is closely related to the Khmer word barang.
In Tamil, the word that refers to Europeans (most specifically to the British) is parangiar, presumably because Tamil does not have the "F" sound. Many South Asian and Southeast Asian languages, including Hindi-Urdu and Malay, also use this word to denote foreigners.