| Mk | Entry | Card | Episode |
| zabathu, Andorian. | 059.02N.[S | Pen Pals. [TNG] | |
| zabathu, Andorian. | 105.1A | Pen Pals. [TNG] | |
| zabathu, Andorian. (holographic animals) | 066.34A.f | Pen Pals. [TNG] | |
| zabathu, Andorian. (pet species) | 018.001A.e | Pen Pals. [TNG] | |
| Zabee nuts. | 105.1B | Investigations. [VGR] | |
| * | Zabel. | 105.3A | Vox Sola. [ENT] |
| zabo meat. | 105.1D | Cardassians. [DS9] | |
| zabo meat. (Cardassian recipes) | 013.07-b | Cardassians. [DS9] | |
| zabo meat. (Cardassian zabu m) | 083.03O | Cardassians. [DS9] | |
| Zabo. | 105.1C | Piece of the Action, A. [TOS] | |
| Zadar IV. | 003.3zMM.[I | When the Bough Breaks. [TNG] | |
| Zadar IV. | 105.1E | When the Bough Breaks. [TNG] | |
| Zaheva, Captain Chantal. | 019.02I.[O | Night Terrors. [TNG] | |
| Zaheva, Captain Chantal. | 105.1F | Night Terrors. [TNG] | |
| Zahir. | 018.082-a1 | Darkling. [VGR] | |
| Zahir. | 105.1G | Darkling. [VGR] | |
| Zahl. | 105.1H | Year of Hell, Part I. [VGR] | |
| Zahl. (vessel) | 040.031E.[C | Year of Hell, Part I. [VGR] | |
| Zahl. (vessel) | 040.058. | Year of Hell, Part I. [VGR] | |
| Zahl. (vessel) | 040APP2H.[C | Year of Hell, Part I. [VGR] | |
| Zahra, Yeoman. [CAST] (Zahra, Ensign) | 020.01M.[O | Operation: Annihilate. [TOS] | |
| * | Zai cluster. | 105.1I | Think Tank. [VGR] |
| Zakarian, Commander. | 105.1J | Caretaker, Parts I & II. [VGR] | |
| Zaldans. | 069.018-a | Coming of Age. [TNG] | |
| Zaldans. | 105.1K | Coming of Age. [TNG] | |
| Zalkon. | 003.3zMM.[J | Transfigurations. [TNG] | |
| Zalkon. | 105.1L | Transfigurations. [TNG] | |
| Zalkonians. | 018.186. | Transfigurations. [TNG] | |
| Zalkonians. | 105.1M | Transfigurations. [TNG] | |
| Zalkonians. (ship) | 018.186-a | Transfigurations. [TNG] | |
| Zambrano, Battle of. | 105.1N | Loud as a Whisper. [TNG] | |
| Zan Periculi. | 105.1O | Menage a Troi. [TNG] | |
| Zanthi fever. | 007.21D.[E | Fascination. [DS9] | |
| Zanthi fever. | 105.1P | Fascination. [DS9] | |
| Zanthi fever. (Hidden desires) | 010.10[B | Fascination. [DS9] | |
| Zapata, U.S.S." | 105.1Q | Menage a Troi. [TNG] | |
| * | Zar. | 105.3B | Live Fast and Prosper. [VGR] |
| Zarabeth. | 058.019. | All Our Yesterdays. [TOS] | |
| Zarabeth. | 105.1R | All Our Yesterdays. [TOS] | |
| Zarabeth. (other characters and life forms) | 058.001.ag | All Our Yesterdays. [TOS] | |
| Zarale, Gul. | 105.1S | Homecoming, The. [DS9] | |
| * | zariphean blend. | 105.3C | Breaking the Ice. [ENT] |
| Zaterl emerald. | 105.1T | Devil's Due. [TNG] | |
| Zaynar. | 105.1U | Hunted, The. [TNG] | |
| Zayra IV. | 003.3zMM.[K | Realm of Fear. [TNG] | |
| Zayra IV. | 018.089-a2 | Realm of Fear. [TNG] | |
| Zayra IV. | 105.1V | Realm of Fear. [TNG] | |
| Zayra. | 105.1W | Man Alone, A. [DS9] | |
| Zayra. (Stirring the pot) | 047.17[A | Man Alone, A. [DS9] | |
| Zed Lapis Sector. | 105.1X | Skin of Evil. [TNG] | |
| Zee-Magnees Prize. | 105.1Z | Ultimate Computer, The. [TOS] | |
| * | Zee. | 105.1Y | Prodigal Daughter. [DS9] |
| * | Zeemo, Carl. | 105.1AA | Badda-Bing, Badda-Bang. [DS9] |
| Zef'No. | 105.1AB | Circle, The. [DS9] | |
| Zef'No. (Calondon.") (Kressari) (Freighters) | 040APP1[X | Circle, The. [DS9] | |
| Zef'No. (Calondon.") see 083.01AA | 083.17I | Circle, The. [DS9] | |
| Zef'No. (Calondon.") see 083.17I | 083.01AA | Circle, The. [DS9] | |
| Zefram Cochrane High School. | 105.1AC | Star Trek: First Contact. | |
| Zefram Cochrane High School. (C, Z, H S. SEE: Z C H S) | 083.10X | Star Trek: First Contact. | |
| * | Zek. | 014.12-a | Emperor's New Cloak, The. [DS9] |
| Zek. | 051.05. | Nagus, The. [DS9] | |
| Zek. | 70.025-a | Rules of Acquisition. [DS9] | |
| Zek. | 105.1AD | Nagus, The. [DS9] | |
| Zek. (index) | 001.080. | Nagus, The. [DS9] | |
| Zek. (and the Bajoran Prophets) | 051.05A | ||
| Zek. (Changing the rules) | 051.05[A | Prophet Motive. [DS9] | |
| Zek. (communications office) | 027.15. | Profit and Lace. [DS9] | |
| Zek. (Hupyrian beetle) | 088.11Q | Ferengi Love Songs. [DS9] | |
| Zek. (Kohlanese barley) | 091.10J | Prophet Motive. [DS9] | |
| Zek. (Never trust anyone who places your prosperity above their own) | 014.02A-b | Nagus, The. [DS9] | |
| Zek. (The Ferengi ruler) | 014.02[A | Nagus, The. [DS9] | |
| * | Zek. (The lobes have it) | 043.046APP4[A | Emperor's New Cloak, The. [DS9] |
| zenite. | 018.015-a | Cloud Minders, The. [TOS] | |
| zenite. | 105.2A | Cloud Minders, The. [TOS] | |
| * | zeolitic ore. | 105.3D | Nightingale. [VGR] |
| Zeon. | 003.3zMM.[L | Patterns of Force. [TOS] | |
| Zeon. | 105.2B | Patterns of Force. [TOS] | |
| Zeon. (other groups and races) | 018.001.ap | Patterns of Force. [TOS] | |
| * | Zero Gee Is Fun. | 105.3E | Good Shepherd. [VGR] |
| zero-grav tumbling. | 105.2E | Begotten, The. [DS9] | |
| zero-gravity combat training. | 105.2D | Star Trek: First Contact. | |
| * | Zet. | 105.3F | Renaissance Man. [VGR] |
| Zeta Alpha II. | 003.3zMM.[M | Best of Both Worlds, The, Part I. [TNG] | |
| Zeta Alpha II. | 105.2G | Best of Both Worlds, The, Part I. [TNG] | |
| Zeta Gelis Cluster. | 003.8.[X | Transfigurations. [TNG] | |
| Zeta Gelis Cluster. | 105.2H | Transfigurations. [TNG] | |
| Zeta Gomal IV. | 003.3zMM.[N | Disaster. [TNG] | |
| Zetar. | 003.3zMM.[O | Lights of Zetar, The. [TOS] | |
| Zetar. | 105.2I | Lights of Zetar, The. [TOS] | |
| Zetar. (Fighting for life) | 018.028[A | Lights of Zetar, The. [TOS] | |
| Zetarians. | 018.027-a3. | Lights of Zetar, The. [TOS] | |
| Zetarians. | 018.028. | Lights of Zetar, The. [TOS] | |
| Zetarians. | 105.2J | Lights of Zetar, The. [TOS] | |
| Zetarians. (Death of a race) | 043.024[A | Lights of Zetar, The. [TOS] | |
| Zetarians. (noncorporeal life) | 018.001B.m | Lights of Zetar, The. [TOS] | |
| Zetarians. (spaceborne life forms) | 005.11.j | Lights of Zetar, The. [TOS] | |
| Zetarians. (The end of the Zetars) | 018.028[B | Lights of Zetar, The. [TOS] | |
| Zevians. | 105.2K | His Way. [DS9] | |
| zhian'tara. | 105.2L | Facets. [DS9] | |
| zhian'tara. (index, m c) (Trill past lives) | 001.074.[K | Facets. [DS9] | |
| zhian'tara. (Other joinings) | 009.8[B | Facets. [DS9] | |
| zhian'tara. (Reincarnated) | 009.4[A | Facets. [DS9] | |
| zhian'tara. (Trill Rite of Closure. SEE: z) | 100.21U | Facets. [DS9] | |
| Zhukov, U.S.S." | 031.05A.[H | Hollow Pursuits. [TNG] | |
| Zhukov, U.S.S." | 081.04AC.d | Hollow Pursuits. [TNG] | |
| Zhukov, U.S.S." | 105.2M | Hollow Pursuits. [TNG] | |
| Zibalians. | 105.2N | Most Toys, The. [TNG] | |
| * | Ziegler, Lieutenant Commander. | 029.43D.[U | Imperfection. [VGR] |
| zilm'kach. | 105.2O | Melora. [DS9] | |
| Zimbata, Captain. | 019.02I.[P | Elementary, Dear Data. [TNG] | |
| Zimbata, Captain. | 105.2P | Elementary, Dear Data. [TNG] | |
| Zimmerman, Lewis. | 043.058. | Cloud, The. [VGR] | |
| Zimmerman, Lewis. | 105.2Q | Cloud, The. [VGR] | |
| Zimmerman, Lewis. (Early encounters) | 032.15A[A.a | Projections. [VGR] | |
| Zimmerman, Lewis. (Early encounters) | 032.15A[A.b | Swarm, The. [VGR] | |
| Zimmerman, Lewis. (Holographic Zimmerman) | 043.058[A.a | Projections. [VGR] | |
| Zimmerman, Lewis. (Holographic Zimmerman) | 043.058[A.b | Swarm, The. [VGR] | |
| * | Zimmerman, Lewis. (Mutual respect) | 043.036D[A | Life Line. [VGR] |
| Zimmerman, Lewis. (Personality traits) | 043.057[A.a | Doctor Bashir, I Presume? [DS9] | |
| Zio. | 018.105-b | Chute, The. [VGR] | |
| Zio. | 105.2R | Chute, The. [VGR] | |
| Ziyal. SEE: Tora Ziyal. | 105.2S | ||
| Zlangco. | 105.2T | Battle Lines. [DS9] | |
| * | Zobral. | 105.3G | Desert Crossing. [ENT] |
| Zocal's Third Prophecy. | 070.102-a | Rapture. [DS9] | |
| Zocal's Third Prophecy. | 105.2U | Rapture. [DS9] | |
| Zolan. | 105.2V | Cardassians. [DS9] | |
| Zor Khan. | 105.2W | All Our Yesterdays. [TOS] | |
| \ | Zora Fel. | 105.2Y | Apocalypse Rising. [DS9] |
| Zora. | 68.76-a4 | Savage Curtain, The. [TOS] | |
| Zora. | 105.2X | Savage Curtain, The. [TOS] | |
| Zorn, Groppler. | 058.069. | Encounter at Farpoint, Parts I & II. [TNG] | |
| Zorn, Groppler. | 105.2Z | Encounter at Farpoint, Parts I & II. [TNG] | |
| * | zoth-nut soup. | 105.2AA | Think Tank. [VGR] |
| * | Zozek System. | 105.3H | Q2. [VGR] |
| Zweller, Cortin. | 043.138. | Tapestry. [TNG] | |
| Zweller, Cortin. | 105.2AB | Tapestry. [TNG] | |
| zylo eggs. | 105.2AC | 11001001. [TNG] | |
| * | zymuth gland. | 105.3I | Fight or Flight. [ENT] |
| Zyree. | 105.2AD | Rules of Acquisition. [DS9] | |
| Zytchin III. | 003.3zMM.[P | Captain's Holiday. [TNG] | |
| Zytchin III. | 105.2AE | Captain's Holiday. [TNG] | |
| * | Zyznian church mouse. | 105.3J | Q2. [VGR] |