A "rook" (ostensibly a contraction of "rookie") applies to a nugget who has completed his or her flight training and qualifications, yet is still inexperienced in actual combat.
Kara Thrace teases Helo about flying with a rookie, referring to Boomer (Miniseries).
Ensigns Brent Baxton and Joseph Clark are rooks that completed their training on the flight simulators available on Pegasus and are assigned to Galactica afterwards (Scar).