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".
- 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.
- 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.
- 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.
- 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.