You meet someone and share a deep meaningful gaze. Both of you want to say something but are afraid to do so. This moment is called mamihlapinatapaiThere have been several attempts to translate this Yamana word. For example: "A look shared by two people, each wishing that the other would initiate something that they both desire but which neither wants to begin.". It is the world's "most succinct wordThe Guinness Book of Records considers it the most difficult word to translate briefly into English." and belongs to the South American language of Yamana.

This year, Yamana became extinct. In Chile, 93-year-old Cristina Calderon died. She was the only member of the Yagan community still speaking their native tongue.

International Mother Language Day is a celebration of linguistic diversity. It began in Bangladesh to remember five protesters killed on 21 February 1952, defending their right to speak BengaliThe sixth most-spoken language in the world. In 1952, Bangladesh was part of Pakistan and the government tried to impose Urdu as the national language..

Around 400 languages disappeared last century and half of the remaining 6,500 may be gone by 2100.

For the Yagan people, they have lost more than words. As Calderon's daughter says: "an important part of the cultural memory of our people is gone."

Many linguists argue language influences how we see the world. Yamana is also a store of ancient knowledge about the region. For many indigenous people, language is an essential part of their identity.

This is not just about the past, says linguist David Harrison. "No culture has a monopoly on human genius, and we never know where the next brilliant idea may come from."

Calderon's children were the first generation to grow up speaking Spanish. World languagesGlobal languages that allow people from many different countries to communicate. For example English, Spanish, Arabic and French. offer more opportunities. If language is for communication, some people think it would be better if we used the same one.

According to the Bible, humans spoke one language until God punished them for building the Tower of BabelThey wanted to build a tower that reached up to heaven. It was named Babel (Hebrew, balal, to confuse) because God created a "confusion" of languages.. There have even been attempts to create a universal language, like EsperantoIn English, one who hopes. Constructed in 1887 with simplified grammar to make it quicker to learn. There are around 100,000 Esperanto speakers..

English has close to 200,000 words, more than any other language. This does not mean it is more sophisticated than unwritten vernacularA native language of a particular group of people, often unwritten or unstandardised.. "Most have incredibly complex grammatical systems that far exceed that of English," says anthropologist Mark Turin.

Two-thirds of languages are not written. It is a race against time to record their words, stories and songs. Once gone, it is rare for languages to come back. Hebrew is the only tongue to return from the dead.

There is no word for goodbye in CherokeeA native language of the Cherokee people of North America., only: "I will see you again." With fewer than 2,000 speakers, it is endangered. For some, its fate is inevitable. Others think these languages can and must survive.

Yes: Languages are worlds of experience and wisdom. No word is fully translatable because it expresses something unique about its culture and the people who use it. Each language enriches our world.

No: This is sentimental, languages are not people. They are tools for communication and cooperation. If we all spoke the same tongue, there would be more understanding and less conflict.

Or... It is sad, but we should not confuse the death of a language with its culture. Spanish-speaking Yagans continue to celebrate their culture and Yamana has given the world the word mamihlapinatapai.