UC Army Abbreviation

Unmanned Combat

Unit Cell

A parallelepiped element of crystal structure, containing a certain number of atoms, the repetition of which through space will build up the complete crystal. The smallest three-dimensional volume element from which the crystal can be constructed. The simplest arrangement of atoms or molecules that regularly repeats in a crystal structure.

Unclassified

Information that has not been determined pursuant to E.O. 12958 or any predecessor order to require protection against unauthorized disclosure and that is not designated as classified.