Yeah parapet has all these
medieval connotations, but it's a word I use every day. You'll encounter the word in
civil engineering, when dealing with
box culverts.
The parapet is a
flat piece of
concrete on either side of the
structure. It is
perpendicular to the
ground, and
immediately below the structure's deck. The
box walls intersect the parapet at
right angles.
It's a little
hard to picture, but if you take any
old box and turn in on the
side then
stick a flat piece
straight up from the box on either end, that's what the parapet
looks like.
In box culverts, the parapet usually cracks where the box walls meet the parapet. This is not a
Good Thing.