Here's an alphabetical listing of terms you'll see while browsing lightsaber listings on eBay:
Collectables: Lightsaber hilts that are similar to, but not as detailed as/not the same size as, lightsaber hilt props used in the Star Wars Trilogies.
Concept: Refers to a lightsaber replica based on an artist's design (concept) that either wasn't turned into a movie prop, or was altered (for aesthetic or practical reasons) before being made into a prop. The most famous concept lightsaber, and the only one I've ever seen auctioned on eBay, is Ralph McQuarrie's Obi-Wan Kenobi design, which was based on the description in the original Star Wars novel. It has a much larger emitter (the disc at the business end of the saber) than the version we're familiar with from the movies, had a chrome finish, and overall made a retro, '50s sci-fi impression.
Conversion: See MRFX Conversion/Mod.
Covertec Wheel: A round, flat aluminum or plastic button on the side of a lightsaber that can fit into a slotted belt clip for costume wear.
Custom: Refers to a lightsaber modified or built from the ground up by a saber smith. Some companies produce custom versions of their own standard products. Independent saber smiths also build custom sabers or customize lightsabers produced by others. The most popular sabers to customize are the MRFX lightsabers. See MRFX Conversion/Mod.
D-Ring: A ring for hanging a lightsaber from a hook on a belt.
EL: Electroluminiscent wire used in some lightsaber blades--it glows when a current is applied to it.
Electroluminescent: See EL.
EL-Ready: A term for a lightsaber hilt that has enough empty space inside it and an emitter hole of the correct size to accept an EL blade.
Graflex: The brand of photographic flashgun on which the original Luke Skywalker Episode IV/Anakin Skywalker Episode III lightsaber was based.
Hasbro: Toy manufacturer that produces "Light and Sound Lightsabers," which have light-up blades, sound effects, and may also have other features such as digitized voices of Star Wars characters. Hasbro sound modules are often used by builders of custom lightsabers to provide their models with sound effects.
HB: See Hasbro.
HB Sound: See Hasbro.
Heiland: The brand of photographic flashgun on which the original Darth Vader lightsaber hilt was based.
HK Larbel: A formerly independent builder of replica lightsaber hilts, now employed by Master Replicas. Some Larbel hilts have plasma or EL blades; others are "EL-ready."
Larbel: See HK Larbel.
LED: Light-Emitting Diode, an electronic component that radiates light when a current passes through it. More durable and efficient than incandescent bulbs. Common brand names are LumiLED and Luxeon. LEDs are used in MRFX lightsabers and in conversions/mods, and in some custom lightsabers.
Light-Emitting Diode: See LED.
Lightec Industries: A maker of EL lightsabers. Newer models use a modular system that allows users to mix and match parts to a certain degree. Most Lightec sabers are inspired by the Star Wars films without closely copying any particular character's lightsaber. Newer Lightec sabers can be fitted with a sound module. Lightec Industries lightsabers are occasionally auctioned on eBay.
LumiLED: A line of LEDs popular with builders of custom lightsabers before the Luxeon Star LEDs became available.
Luxeon: See Luxeon Star
Luxeon Star: A line of LEDs that is attached to a star-shaped base. Popular with builders of custom lightsabers and MRFX conversions/mods.
Master Replicas: A company that produces lightsaber replicas, lightsaber collectables, and other movie memoribilia.
Mod(ification): See MRFX Conversion/Mod.
MR: See Master Replicas.
MRFX, MR FX: Acronym for "Master Replicas Force FX," a line of collectable lightsabers based on famous models from the Star Wars Trilogies. Force FX lightsabers have polycarbonate blades that conceal strings of LEDs that power on and off sequentially (to mimic the extend/retract effect seen in the movies) and integrated circuit boards with shock sensors that produce lightsaber sound effects from the movies: power-up/-down, clash, and idle hum. Force FX lightsabers are frequently auctioned on eBay.
MRFX Conversion/Mod: A Master Replicas Force FX lightsaber that has been rebuilt by a saber smith to be sturdy enough for dueling. Because the string of LEDs in an MRFX saber blade is fragile, the string is removed and one larger LED is mounted in the hilt. Most conversions have removable blades. A number of eBay members now produce and sell MRFX conversions.
Parks Sabers: Well-known maker of EL lightsabers, many of which closely resemble famous lightsabers from the Star Wars films. Most models do not have sound. Parks lightsabers are occasionally auctioned on eBay.
Plasma blades: Blades that contain fragile glass tubes full of gases that can be exited by an electric current and made to glow.
Polycarbonate blades: Tough tubes outfitted with a light-diffusing film. Come in two diameters, 3/4 inch and 1 inch, and several wall thicknesses. Can house a wire for an EL lighting system, a string of LEDs (used in MRFX sabers), or can be "empty" (lit by a hilt-mounted LED, such as in an MRFX conversion or a custom-built saber). EL systems use 3/4-inch tubes; MRFX sabers and conversions, and most LED sabers, use 1-inch tubes. (Some custom-built LED sabers use 3/4-inch tubes, however). Polycarbonate blades can be used for dueling as long as they do not contain fragile strings of LEDs as the unmodified MRFX blades do. Except in unmodified MRFX sabers, most polycarbonate blades are removable.
Replicas: Lightsaber hilts made to look as much like the props used in the Star Wars Trilogies as possible. Replicas can be made to look like the "pretty" designs used in closeups or like the more rugged but less detailed designs used for stunt scenes.
Rubies: A company that produces plastic lightsabers for costume wear. These usually have blades made of telescoping plastic tubes that retract all the way into the hilts and are lit by a concealed flashlight bulb. They do not have sound effects.
Stunt: Refers to a saber designed primarily for dueling. Top considerations are durability and a clean hilt design that lacks buttons or other features that would impede the use of fencing moves. Stunt sabers have blades made of aluminum, carbon fibers, or acrylics or other tough plastics. Most stunt sabers do not produce any sound effects, because they are intended as props for choreographed action sequences in fan films. It is assumed that the film makers will animate illuminated blades over the props and add sound effects in post-production.