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- Uaenn Ei'krih Outpost
- Uagoh
- Uaierex
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- Ubea system
- Ubean
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- Ubo
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- Uexueem
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- Ugilh
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- Unk
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- Unlicensed publications
- Unlimited, Issue 1
- Unlimited, Issue 10
- Unlimited, Issue 2
- Unlimited, Issue 3
- Unlimited, Issue 4
- Unlimited, Issue 5
- Unlimited, Issue 8
- Unlot
- Unnamed Ajir
- Unnamed Akira class starships
- Unnamed Alpha and Beta Quadrant starships
- Unnamed Andorians
- Unnamed Angelou class starships
- Unnamed Arcadians
- Unnamed Arkenites
- Unnamed Armitage class starships
- Unnamed Bajorans
- Unnamed Battlehawk class starships
- Unnamed Benthans
- Unnamed Benzites
- Unnamed Betelgeusians
- Unnamed Bolians
- Unnamed Borg
- Unnamed Borg cubes
- Unnamed Borg diamonds
- Unnamed Borg obelisks
- Unnamed Borg rectangles
- Unnamed Borg spheres
- Unnamed Borg starships
- Unnamed Borg tactical cubes
- Unnamed Breen
- Unnamed Bwujans
- Unnamed Caitians
- Unnamed California class starships
- Unnamed Caratu
- Unnamed Cardassian starships
- Unnamed Cardassians
- Unnamed Chandir
- Unnamed Changelings
- Unnamed Constitution class starships
- Unnamed Courage class starships
- Unnamed D'deridex class starships
- Unnamed D5 class starships
- Unnamed D7 class starships
- Unnamed DTI personnel
- Unnamed Dauntless class starships
- Unnamed Deep Space 9 personnel
- Unnamed Delta Quadrant stars and systems
- Unnamed Deltans
- Unnamed Dominion starships
- Unnamed Draylaxians
- Unnamed Dresselhaus type starships
- Unnamed E class space stations