CO: Commanding officer (a.k.a your husband/wife’s boss).
Det: Detachment. A scheduled, brief period of time in which his unit/squadron leaves the homebase for training.
Duty: A position of watch filled at regulated intervals by military personnel.
MILSO: Military Significant Other.
PCS: Permanent Change of Station. A move between one duty station and another.
S/O: Significant Other.