- Admiral
- Admiral's log
- Admiral's log, USS Enterprise (NCC-1701)
- Admiral's personal log, USS Enterprise (NCC-1701)
- Admiral-superlative
- Adobe
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- Adon, son of Gorath
- Adonolo
- Ador
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- Adrian
- Adrian's Bane
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- Adriana Berardi
- Adrienne Kuwano
- Adrienne Markham
- Adrienne Soranno
- Adrik Thorsen
- Adrokos
- Adronn feltara
- Adult (Species M-113)
- Adulux
- Adun cactus
- Advance
- Advance class
- Advanced Borg drone
- Advanced Robotics Institute
- Advanced Security Techniques
- Advanced Starship Design Bureau
- Advanced Tactical Training
- Advanced Warp Development Group
- Advanced command cruiser
- Advanced cruiser
- Advanced dreadnought
- Advanced heavy carrier
- Advanced long-range torpedo
- Advanced research vessel
- Adventure
- Adventure Book
- Adventure Gaming in the Final Frontier
- Adventures in Jazz and Time
- Adventures in Time and Space
- Adventures in the 32nd Century
- Adventures in the 32nd Century, Issue 1
- Adventures in the 32nd Century, Issue 2
- Adventures in the 32nd Century, Issue 3
- Adventures in the 32nd Century, Issue 4
- Advisors (STO)
- Advocate
- Adya
- Aecupus
- Aegian class
- Aegis
- Aegis (disambiguation)
- Aegis Aquila
- Aegis class (20th century)
- Aegis class (23rd century)
- Aegreth Mrith
- Aegris
- Aehallh worm
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- Aeioyum
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- Ael t'Rllaillieu
- Aela
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- Aelas IV
- Aelasan
- Aeliqha
- Aelont
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- Aenar Council
- Aenar Ministry of Health
- Aenar compound
- Aeneid
- Aenni
- Aennik Okeg
- Aentrilaar
- Aeolian
- Aeolus (myth)
- Aeolus class
- Aeon
- Aeon (material)
- Aeon (mirror)
- Aeon VI
- Aeon system
- Aeorethian
- Aerel
- Aerial Guard
- Aerial strategy simulation
- Aerie
- Aerie class
- Aerimea
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- Aferva
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- Affliction
- Afgar
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- Aflor
- Africa
- African Confederation
- African violet
- Afritalis
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- After Darkness
- After Darkness, Part 1
- After Darkness, Part 2
- After Darkness, Part 3
- After action report
- After the Ball
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- Aftermath
- Aftermath, Issue 1
- Aftermath, Issue 2
- Aftermath, Issue 3
- Aftermath (comic)
- Aftermath (compilation)
- Aftershock
- Aftershocks
- Afya Jamilia
- Ag'hel
- Agachi
- Again, Troublesome Tribbles
- Again, the Ears
- Against Their Nature
- Agamemnon
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- Agan
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- Agbadudu
- Agbar
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- Age of Heroes
- Age of Lament
- Age of Makto
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- Age of the Empress
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- Agena IV
- Agent 201
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- Aggarath Simparri
- Aggregation of Rigellian Systems
- Agguggt!
- Aghan
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- Agiirrat
- Agmar
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- Agnatha
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- Agoni
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- Agonite space eagle
- Agonizer
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- Agony of Zchol
- Agora (disambiguation)
- Agorva Reshtarc
- Agosto Caitano
- Agovanli
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- Agricultural scientist
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- Agurtha
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- Ahrens
- Ahrmant Wyoss
- Ahrrek
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- Ahwahnee class
- Ahzdar
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- Ahzdar (star)
- Ai'lara Jarok
- Aia
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- Aia'vadi
- Aibut
- Aida Selzner
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- Aide
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- Aidoann t'Khnialmnae
- Aidulac
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- Aijiuot
- Aiken
- Ailam
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- Aileer
- Aili Lavena
- Ailig
- Ailig IV
- Ailoi
- Ailur
- Ailurus lizard
- Aimee Ford Foster
- Aimoto
- Ain
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- Ain I
- Ainad Secori
- Ainaro
- Aindar Drexa
- Aindia
- Aindira Drexa
- Aindrea Baxter
- Aine McAvennie
- Ainsarri Simparri
- Air-bum
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- Airlock
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- Aiseo
- Aiti
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- Aivilla Mrith
- Aiyahl lock
- Aiyizun
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- AjElasi
- Ajabwe
- Ajanian
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- Ajard vestai-Rondal
- Ajax
- Ajilon
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- Ajir