The announcement that happened today on a WHO conference in Geneva, comes almost six weeks after the virus was first identified in the city of Wuhan, China, in late December.
Since then the death toll from the virus passed 1,000. Tens of thousands of people have been infected as the virus becames more global and threatening.
The word coronavirus refers to the group of viruses it belongs to, rather than the latest strain.
Researchers have been calling for an official name to avoid confusion and stigmatisation.
"We had to find a name that did not refer to a geographical location, an animal, an individual or group of people, and which is also pronounceable and related to the disease," the WHO chief said.
"Having a name matters to prevent the use of other names that can be inaccurate or stigmatising. It also gives us a standard format to use for any future coronavirus outbreaks."