‘’Washbasin’’ is another term of ‘’sink’’, or ‘’basin’’, or a bowl fitted with a water supply and a drain for cleaning hands, face washing, etc.
Some kinds of sinks are mounted permanently on the wall, or installed on an obsolete piece of furniture, otherwise they are made to standing on the floor.
Washbasins usually are made of porcelain, ceramic, stone, glass, or concrete, etc.
If you want to learn more about what concrete washbasins means, explore below the Urbi et Orbi  washbasin collection.