Dorsal
From Memory Alpha, the free Star Trek reference.
Dorsal refers to the topside of a body and the term is commonly used in defining the top of a starship. This nomenclature is necessary while functioning in the three dimensions of space.
During Shinzon's attack on the USS Enterprise-E in 2379, the starship's dorsal shielding failed as the result of a focused attack. (Star Trek Nemesis)
