December 18th. Since 2012. When the UN decided to adopt it as its 6th official language.
The Arabic language is a pillar of the cultural diversity of humanity.
It is one of the most widely spoken languages in the world, used daily by more than 290 million people.
World Arabic Language Day is celebrated every year on 18 December since 2012.
The date coincides with the day in 1973 that the General Assembly of the United Nations adopted Arabic as the sixth official language of the Organization.
Message from the Director – General
“Arabic is a bridge between cultures and across borders – a true language of diversity. (…) on this international day, UNESCO will celebrate and explore the role of Arabic language academies. Not only do these institutions preserve, enrich and enhance the Arabic language, they also help monitor its use in conveying accurate information in the context of global current events.”
— Message from Ms Audrey Azoulay, Director-General of UNESCO
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The poster for World Arabic Language Day is an artwork of the Tunisian calligrapher Karim Jabbari which illustrates the following piece of poetry
“He who imbued languages with the highest qualities
Bequeathed to Arabic the secret of beauty“
— Ahmed Chawqi
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source: all text and images from en.unesco.org