orga - para
- oxygen mask eject switch
- oxygen pipeline
- oxygen pressurization
- oxygen pump housing
- oxygen replenishing equipment
- oxygen servicing truck
- oxygen supply
- oxygen supply cylinder
- oxygen tank
- oxygen user
- oxygen valve
- ozone absorption
- ozone bomb
- ozone layer
- ozonization
- ozonopause
- p n diode laser
- p n junction light modulator
- p n junction semiconductor laser
- pacific air force command
- pacific area communication system
- pacific barrier patrol
- pacific fleet all weather training unit
- pacific launch operations office
- pacific missile range facility
- pacific missile range representative
- pacific missile range tracking facility
- pacific range electromagnetic signature studies for ballistic missile
- pacific region
- pacific wing of naval air transport service
- pack artillery
- pack bridge
- pack decontamination apparatus
- pack gun
- package
- package weight
- package with decontamination substances
- packaged magnetron
- packaged stock of fuel
- packaged water
