The commander-in-chief's aide-de-camp
An aide-de-camp was an adjutant who performed secretarial duties for a high-ranking official.
In 2293, the Starfleet commander in chief's aide-de-camp introduced him at the classified briefing at Starfleet Headquarters regarding talks with the Klingon Chancellor Gorkon. (Star Trek VI: The Undiscovered Country)
The character's function was not identified on-screen but rather she was referred to as such in the film's end credit sequence.