Asteroid 6820, Buil, was discovered on December 13, 1985 at the observatory known as CERGA (Centre de recherches en géodynamique et astrométrie, or Center For Geodynamic and Astrometrical Research) at Caussols, Alpes-Maritimes, France. The observatory gets the discovery credit. Asteroid Buil has a period of 4 years, 300 days.
It was named for prominent French amateur astronomer and astronomical software author Christian Buil.
Christian Buil
"Buil" is a Dutch word referring to a blow.
Henk Middleraad links asteroid Buil to unexpected blows.