Theta

;Astronomical nomenclature
* Delta Theta III, a planet
** Delta Theta III aborigine
*** Delta Theta III aborigines
** Delta Theta III entity
* Omicron Theta star system
** Omicron Theta, a planet
*** Omicron Theta colony / Omicron Theta outpost
* Theta III, a planet
* Theta VII, a planet
** Theta VII colony, a colony 
* Theta 116 solar system, a star system
** Theta VIII, a planet
* Theta Amano Trade Center
* Theta Bowles, a star
* Theta Centauri, a star system
* Theta Curry, a star
* Theta Cygni XII, a planet
* Theta Gentle, a location
* Theta Gluckstern III, a planet
* Theta Helios, a planet
* Theta Hulett, a location
* Theta Hydrae, a star system in the Beta Quadrant
* Theta Indi, a star system
* Theta Mees, a location
* Theta Omicron IV, a planet
* Theta Pegasi, a star system
* Theta Zeta, a planetoid
* Theta Zibal III, a planet
;Codes
* "La Forge-theta-2-9-9-7", used to override operational safety limits and to verify priority clearance
* Theta-3, a decryption protocol on a Borg ship
* "Theta-alpha-2-7-3-7-blue", used by Riker to access Data's schematics
* "Worf theta-6-1-9", used to override holodeck lockout
;Designations
* Theta (classification), a Terran slave classification for the Alliance in the mirror universe
** "0413 Theta", a slave designation
;File names
* Kim Sports Program Theta-2, a holodeck program
* "Theta-12-alpha", computer medical file 
* "Theta-15", filename where The Doctor's original holodeck program was stored
;Locations
* "6-theta-9", a location on the USS Voyagers deck 4
* "87-theta/271", spatial coordinates of Voyagers location
* "Grid 124, Octant 22-theta", Borg designation for origin of Species 6339
* "Theta-1-6", a section location on a planet
;Science and technology
* "Omicron theta", a sensor band
* "T = C1/θ(P)E", a math equation
* "Theta 309", a subspace band
* Theta-band / theta-band radiation / theta radiation / theta radiation field
** Theta-band device, a device used to generate theta-bands
** Theta core
*** Theta storage tank / theta tank, used to house theta radiation
** Theta radiation poisoning
* Theta band filter, used on a Fournier scan
* Theta band frequency, a subspace communications frequency
* Theta class (planetoid), a type of planetoid
* Theta class (starship), a type of raider
* Theta-matrix compositor, assists in recrystalizing dilithium
* Theta flux distortion
* Theta wave, type of brain waves
* Theta-xenon, a chemical element
;Tactics
* "Pattern theta", attack pattern used by Benjamin Sisko aboard a runabout to destroy the wormhole in a Dominion simulation; also ordered by Sisko for Federation fighters against the Dominion
** "Pattern Shinzon theta", Shinzon's signature attack pattern
* "Pattern theta", an evasive maneuver against the Cardassians
** "Pattern theta-1", used by Tom Paris to evade the Praylor
** "Pattern theta-2", used by Chakotay to evade the Kazon
* Theta formation, ordered by Sisko for Federation fighters
fr:Thêta