From WordNet (r) 3.0 (2006) [wn]:
mural
adj 1: of or relating to walls; "mural painting"
n 1: a painting that is applied to a wall surface [syn: mural,
wall painting]
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Mural \Mu"ral\, a. [F., fr. L. muralis, fr. murus wall. See
Mure a wall.]
1. Of or pertaining to a wall; being on, or in, a wall;
growing on, or against, a wall; as, a mural quadrant.
"Mural breach." --Milton. "Mural fruit." --Evelyn.
[1913 Webster]
2. Resembling a wall; perpendicular or steep; as, a mural
precipice.
[1913 Webster]
Mural circle (Astron.), a graduated circle, in the plane of
the meridian, attached permanently to a perpendicular
wall; -- used for measuring arcs of the meridian. See
Circle, n., 3.
Mural crown (Rom. Antiq.), a golden crown, or circle of
gold indented so as to resemble a battlement, bestowed on
him who first mounted the wall of a besieged place, and
there lodged a standard.
[1913 Webster]