The Glossary of Terms denotes common words and phrases used within the series and on the Wiki.
- Alien: Any creature not native to Earth.
- Altea: A planet destroyed 10,000 years ago. Home of the Alteans.
- Altean: A native resident of Altea.
- Arena: The gladiatorial ring where slaves fight for Zarkon's entertainment.
- Arusian: A native resident of Arus.
- Balmera: A massive petrified creature that has become a living planet. Home of the Balmerans.
- Balmeran: A native resident of a Balmera.
- Bridge: The command center of a large spacecraft from where it is piloted.
- Castleship: A spacecraft that acts as a support and transport ship as well as a castle.
- Central Command: The home base of the Galra Empire.
- Drone: Small floating robots used for patrols, attacks, and repairs. The most notable Drone is Rover.
- Druid: A member of Haggar's mysterious covenant that appears to have magical abilities.
- Earth: A planet in the Milky Way galaxy. Home of the human race.
- Earthling: A native resident of Earth, most notably a human.
- Fighter Jet: A smaller spacecraft used by the Galra Empire for patrols and battle piloted by Sentries. Also known as "fighters", "patrol(s)", "patrol jet".
- Flight Pod: A small spacecraft used mainly for quick transport. May also be called an "escape pod".
- Food Goo: The green goo consumed by Alteans as food in the Castle of Lions.
- Galaxy Garrison: An organization tasked with training Earthlings for exploring space.
- Galra: The Galra Empire, or an individual or thing associated with the Empire.
- Galran: An alien of purple skin or fur with yellow eyes most often seen as a member of the Galra Empire.
- Gladiator: Usually spoken in reference to either:
- Lion: One of the robotic Lions of Voltron.
- Nunvill: A drink enjoyed by Alteans, described as "the nectar of the gods" that tastes like "hot dog water and feet". It can be used as a hair tonic to make hair flourish.
- Planetoid: A small planet, not necessarily spherical in shape. "Another term for asteroids, which are also called minor planets".
- Pod: Usually spoken in reference to either:
- Flight Pod: A small spacecraft used mainly for quick transport.
- Sleep Pod: A small device used for stasis sleep and healing.
- Power Crystal: A Crystal produced by Balmera with enough energy to power spacecrafts. The largest and rarest are known as "Battleship-class" Crystals.
- Quiznak: An expletive used by Coran and adopted by Lance and the other Paladins. It literally means "dang it". Hence, Lance tells Keith to "Shut your dang it". Strangely, it can be also used as an adjective, as in "quiznaking Galra".
- Quintessence: A mysterious substance that appears to act as a "life force" for living things.
- Sentry: A bi-pedal robot used by the Galra Empire. Sentries act as guards, army units, pilots, and general workers; they are capable of speech and communicating with each other.
- Scaultrite: A valuable material produced by a weblum. It is used for various things, but most notably to convert Altean energy to power teleduv devices used to create wormholes.
- Sleep Chamber: The chamber in the Castle of Lions containing sleep pods. Also known as the "Infirmary".
- Sleep Pod: A pod notably seen in the Castle of Lions for putting someone into a stasis sleep and healing their wounds. Also known as a "Cryo-Replenisher".
- Tick: A time slice comparable to a "second"; how well they match up is unknown.
- Teleduv: A device built with scaultrite disks and powered by Altean energy to create wormholes for traveling through space.
- Training Deck: The area of the Castle of Lions where Paladins train.
- Voltron: The most powerful robot in the universe comprised of five robotic Lions.
- Voltron Alliance: Planets that have formed an alliance of protection with the team behind Voltron.
- Weblum: An enormous worm that travels through space and consumes dead planets. It produces a valuable material called scaultrite.
- Warship: A large spacecraft used by the Galra Empire and owned by Galra Commanders. Also known as a "battleship".
- Wormhole: A hole in spacetime used to instantaneously transport people and things from one area in the universe to another.
- Yalmor: A creature described to travel as a pack by Coran, and that might feed each other of its kind. It is compared to the Paladins of 10,000 years ago to exemplify the strong bond they shared.