Occasionally I might slip in some LEGO terminology in one of my posts. This page lists a bunch of terms you’ve probably not heard before, but can be helpful if you go to a LEGO event or talk to a LEGO fan. It’s definitely not the complete list, so if I’ve missed something, let me know and I’ll add it in.


  • ABS: Acrylonitrile butadiene styrene. The plastic that makes up our favourite past-time. This stuff is tough and heat resistant. We love ABS.
  • AFOL: Adult Fan Of LEGO. Pretty much anyone over 18.


  • Baseplate: Large, flat plates filled with studs. Used as the starting point for a build. LEGO parts can be attached to the top, but not the bottom.
  • Bigfig: Moulded figure bigger than a minifig. Ones like The Hulk, Wampa, Trolls etc are all Bigfigs.
  • Billund: Billund, Denmark. The headquarters of The LEGO Group (TLG)
  • Bley: Blueish Grey. Fans use bley where TLG use Stone Grey and all it’s variants.
  • BOLOCs: Built Of Lots Of Colours. A model with loads of different colours. What we all probably built as kids. See also: Rainbow Warrior
  • Brick(s): The guts of LEGO. Available in lots of different sizes and colours, other parts with studs can be attached on both the tops and bottoms of bricks.
  • Brick Built: Part of a LEGO build that is made up of multiple LEGO elements, instead of the single, pre-fabricated piece eg. a brick built door made out of plates instead of the pre-fab single element door and frame.
  • Build: The name given to a set or MOC.
  • BURP: Big Ugly Rock Piece. A single piece pre-fab rock-wall type piece. Goes with a LURP.


  • Cheese Slope: LEGO part number 50746. They are a 1×1 tile with a 33 degree slope, going to 2 plates or 2/3 of a brick high. Called a cheese slope/cheese wedge/cheese block because the orange and yellow ones look like a wedge of cheddar.
  • Custom: Parts or elements that aren’t officially produced by TLG, but is still considered LEGO. They can include stickers, paints or accessories and minifigs from third parties like BrickArms and BrickForge etc. Purists don’t like them.


  • Dark Ages: The time in a LEGO fan’s life where they wander away from the way of the brick, in pursuit of non-LEGO things. Most of the time for university and being somewhat responsible for other people and property. They come back though – hopefully!
  • Design ID: The number TLG assigns to a specific part. These dictate the shape, but not the colour.


  • Element (and Element ID): The official name for each unique LEGO piece. The Element isn’t just the shape (see Design ID), but also the colour. Each unique combination is given an Element ID, so there are heaps!
  • Erling Brick: The wonderful Erling brick (or the headlight brick, washing machine) is one of the favourite SNOT elements thanks to it’s freaky weird design. It was designed by Erling Dideriksen back in 1979.


  • Greebling/Greebles: The extra small, visual elements added to the surface of a build to make it look nice and interesting. Commonly used in sci-fi builds.


  • Half Stud Offset: A building technique that lets a LEGO fan create something while ignoring the standard stud alignment on a plate. The use of jumper plates allows this.
  • Hassenpin: Unofficial name for Part 55615: 3×3 Technic Right angle bend with 4 pins. Designed for the LEGO Mindstorms 2nd generation by LEGO Mindstorms User Panel (MUP) member Steve Hassenplug.


  • Inventory: The list of parts included in a LEGO set. Inventory lists can be seen on sites like Brickset.com


  • Jumper Plate: The fantastic brick that’s either a 1×2 plate with one stud in the middle, or a 2×2 plate with 1 stud in the middle. Redesigned in 2014. Used in Half Stud Offset builds. Jumper plates are tops.


  • LDD: LEGO Digital Designer. Free software for PC and Mac used to create virtual LEGO models.
  • LEGO: This seems to be a pretty obvious one, but I’m focusing more on the capitalisation here. LEGO is intended to be written in all caps.
  • Legos: Hush! The official plural term for more than one LEGO element is “LEGO brand building bricks” but saying that is crazy nonsense. LEGO fans know one or more bricks as LEGO, like the grammatical convention for “sheep”. Anyone heard saying “Legos” is an imposter and should be dealt with swiftly. Or educated. Or both.
  • Licensed Theme: Themes based on an existing licensed idea. Star Wars, The Simpsons, Lord of the Rings etc are all licensed themes.
  • LUG: LEGO User Group. Local or regional clubs that meet and do things together. They’re officially supported by TLG, so join one near you!
  • LURP: Little Ugly Rock Piece. The top half of the mountain that goes with a BURP.


  • Macaroni brick: The quarter circle brick – looks like a piece of macaroni.
  • Microfigure: Tiny figures seen in the LEGO Games series or as trophies in regular sets.
  • Microscale: Refers to builds that are built smaller than minifig scale.
  • Minidoll: The people that come with LEGO Friends sets. Often thought of by AFOLS as either weird, a waste, or an abomination.
  • Minifigure (and Minifigure Scale): Also known as minifigs. The people created by TLG that populate the sets. Ridiculously collectible, with some being very rare and expensive. Minifigs come standard with detachable legs, torso and head. Many also include accessories like hats, tools and more. Minifig scale is a build suited for minifig population.
  • MISB: Mint In Sealed Box.
  • MOC: My Own Creation. LEGO creations built without instructions. Pronounced as “mock”.
  • Modulars: A series of sets aimed at AFOLs. The sets are of a multi-storey building with removable storeys and detailed rooms, at minifigure scale. One has been released every year since 2007. Well loved by AFOLs due to their interesting and rare parts, and great build techniques. Called Modulars because other storeys can be added, and modifications can be added easily. Old Modulars are extremely pricey and can fetch for anything up to $1500 online.
  • MSRP: Manufacturer’s Recommended Selling Price. The official price set by TLG. Varies between countries, and occasionally between retailers.
  • MUP: LEGO Mindstorms User Panel. A panel of LEGO Mindstorms users who came on board to help create the second generation of Mindstorms products.


  • PAB: TLG’s site for buying individual elements.
  • PAB Wall: The wall of glory at physical LEGO stores. These are walls full of different LEGO elements. Fill up a cup to buy what you need!
  • Plate: Different to a baseplate, these are flat elements (one third height of a brick) of varying sizes that can have other elements attached to both the top and the underside.
  • Polybag: Small plastic bags used for minifigures and small sets. These are often promotional products or giveaways.
  • POOP: Parts Out of Other Parts. Often a large, ugly piece that could be made to be more aesthetically pleasing if it were brick built. This normally is seen as a dumbing-down of the system.
  • Purist: A LEGO fan who only buys and uses official LEGO products.


  • Rainbow Warrior: Those of us (usually much younger) who created builds out of a wide range of colours. See BOLOCs.


  • S@H: LEGO’s online store shop.LEGO.com. Used to be called Shop at Home.
  • Set: A product released by TLG containing parts, instructions, and most of the time, minifigures.
  • Sig-fig: The minifigure version of a fan, used in online communities as an avatar.
  • SNOT: Studs Not On Top. A building technique that allows LEGO elements to be placed on their sides or upside-down so the studs aren’t on top.
  • STAMP: Stickers Across Multiple Pieces. Very sad to see as the pieces are not able to be separated without ruining the sticker.
  • Stud: The round bumps on the tops of LEGO elements. Used as a measuring unit “this model is 20 studs long”.
  • Swooshability/Swooshable: The “thing” about the build that just makes you want to pick it up and fly around the room making swoosh noises.
  • System: Groups of elements designed to connect to each other. There are a few different systems, including Technic and Duplo, as well as the main system.


  • Technic: Introduced in 1977, Technic consists of different parts like gears, axles and rods, allowing functioning mechanical models to be built. Mostly compatible with the main System.
  • Theme: A related line of sets and minifigures released by TLG. City, Space etc.
  • Tile: A LEGO piece the same thickness as a plate, but without studs.
  • TLG: The LEGO Group. The parent company for all LEGO brands around the world.


  • UCS: Ultimate Collectors’ Series. A fantastic series of big LEGO Star Wars sets designed for teens and adults.