What does O & D stand for?

Origin and Destination [Aviation]

Ordering and Distribution (SAUS)

Organization & Deployment (SAUS)

On Deck (KSC)

On Dock (MCD)

Operational Difficulty (ACAE)

Order of Deportation

Obstacle-Dominance [Medicine] (DMAA)

Zero Dimensional (AAEL)

Origin and Destination (AD)