mu ‧ ral /ˈmjʊərəl $ ˈmjʊrəl/ BrE AmE noun [countable]
[ Date: 1500-1600 ; Language: Latin ; Origin: muralis 'of a wall' , from murus 'wall' ]
a painting that is painted on a wall, either inside or outside a building ⇨ fresco
—mural adjective [only before noun]