Language boundary

A language border or language boundary is the line separating two language areas. The term is generally meant to imply a lack of mutual intelligibility between the two languages. If two adjacent languages or dialects are mutually intelligible, no firm border will develop, because the two languages can continually exchange linguistic inventions; this is known as a dialect continuum. A "language island" is a language area that is completely surrounded by a language border.

The concept of mutual intelligibility is vague. More important, the ability to distinguish languages from one another can also be difficult, since some languages share writing systems but are spoken differently and some are identical when spoken but are written using different alphabets. There are often also shared terms between two languages even between languages that have nothing to do with each other.

For example, Spanish is spoken in most Central American and South American countries, but also in Spain. There are subtle but recognizable differences between the dialects, but there are different dialects even within the country of Spain. In many cultures there are still subtle differences between the terminology (called the register) used when talking to your boss and talking to your mother or talking to your friends. So where are the language borders?

There can also be people within a country who speak the "native" language of a different country, some of whom may be bilingual. Also, an inherited language may evolve and perhaps absorb some of the characteristics or terms of the new area's predominant language. In cases such as these, it becomes even more difficult to identify specific languages.

When speakers have a foreign accent, they are often perceived to be less intelligent and are less likely to be hired. It is the same with an accent from a peripheral area, rather than the accent from the urbanized core: a peripheral person is typically perceived as speaking a "less correct" by those who are more educated, while those who are not as educated do not perceive any difference in the "correctness". Colonial histories could also help this phenomenon.

A well-known example of a language border is the border between Romance languages and Germanic languages that stretches through Belgium, France, Switzerland, and Italy.

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