The virus looks like a crown under microscope and Corona means crown, hence the name, Corona Virus.
Coronavirus disease (COVID-19) is an infectious disease caused by a new virus that had not been previously identified in humans.The virus causes respiratory illness (like the flu) with symptoms such as a cough, fever and in more severe cases, pneumonia.

There are other viruses in the corona family. That is why the one we are currently faced with has it’s unique name, COVID 19. ICTV announced “severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)” as the name of the new virus on 11 February 2020.
Disease
coronavirus disease
(COVID-19)
Virus
severe acute respiratory syndrome coronavirus 2
(SARS-CoV-2)