Ever wonder what the difference between a brick and a tile is? What LUGs are, and why your efforts are deemed BOLOCS? Fret no more, our little Lego lexicon explains the basics. From A to, well, currently we stop at W. And if you do have additions, please do not hesitate to leave a comment …


ABS – common abbreviation for Acrylonitrile Butadiene Styrene, the hard plastic that most Lego parts are made off.

AFOL – acronym for “Adult Fans (or Friends) of Lego”.

Architecture – Lego sets recreating famous landmarks … at a slightly high price. There are also “creative sets” that allow architects to easily build mock-ups of their projects, all in white Lego bricks.


Baseplates – the foundation upon which a project is created, usually thin plates with studs on top, but no connection possibility on the bottom side. Specialized baseplates may incorporate landscape designs, and are usually found in larger Lego sets.

Billund – town in northern Denmark, where the Lego headquarters and the original Legoland are located.

Bionicle – Lego’s own series plugging into the whole “Mecha” mythos.

Bley – the blueish grey Lego uses for some modern bricks, as compared to “old grey”.

BOLOCS – acronym for “Built of Lots of Coulours”. This is a slightly derogatoray term used by some AFOLs when describing models that incorporate a wide colour palette, the way children tend to use Lego.

Brick – the basic brick that made Lego such a legend, by now available in a wide variety of sizes and colours. Other bricks or pieces can be attached to the top or the bottom.

Brick-Built – any Lego model that is built by exclusively using the standard bricks, but no special pieces.

BURP – acronym for “Big Ugly Rock Piece”, a five-brick-high special piece used to create rock faces or similar.

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Cheese Slope – a special Lego piece with a 33 degree slope. The yellow variety looks like a wedge of cheese, hence the name.

Chima – an interactive Lego series, where characters are anthroipomorphic animals, somewhat drawing heavily from Asian mythology at times.

Classic – the very basic Lego range, the sets are an ideal introduction for KFOLs (and others … to be honest).

Clear Bricks – translucent bricks (or other pieces), that are not really clear at all.

Clone Brands – any manufacturer that somehow imitates the basic Lego principle, whether as a direct (and compatible) copy, or as a concept. Many are cheaper, but also of inferior quality at times. Lego fanatics will not touch clone brands with a very long barge pole, but those with a more relaxed attitude may find some interesting additions to their collection.

Creator – Lego sets that do not fit into any “theme”, but are aimed at KFOLs and TFOLs wanting to explore beyond the Classic range.

Custom Models – any Lego model that uses more than OOB Lego pieces, for instance pieces from clone brands, accessories that are designed by third parties, or even modified Lego pieces (think paint, decals, or even power tools). Again, Lego fanatics might take a dim view of such shenanigans.


Dark Ages – any time in which you are not involved in one way or the other in creating with Lego.

Dimensions – a Lego video game, in which characters from different areas can interact with each other. See our introduction to Lego Dimensions here.

Draft – an organised swap of pieces at the meeting of a LUG.

Duplo – extra-large Lego brick system created for younger kids, some parts may be used with conventional Lego.


Erling Brick – a special 1-stud-brick that has a recess on one side, complete with a stud to facilitate a 90 degree angle in building. Sometimes also knwon as a “headlamp brick”, this brick was named after its inventor, the Lego designer Erling Dideriksen.

Exclusives – Lego sets only available in Lego stores or in their online shop.


Friends – a Lego series aimed squarely at female KFOLs and TFOLs. This series has a range of figures (and corresponding scale) that is somewhat larger than minifigure scale. “Elves” and “Disney” are similar in design.


Greeble – detail added to improve an otherwise uninspiring surface area, often used in large science fiction or steampunk creations.


Half-Stud Offset – building technique that breaks the Lego stud rules by (usually) using a jumper plate, changing the alignment of pieces slightly.

Hero Factory – Lego game system with a strong science-fiction influence, also similar to “mecha” at times.


Illegal Build – any Lego creations that involve breaking the rules Lego set down for their own designers, for instance by bending or not properly connecting pieces. Many custom creations are considered illegal.


Jumper Plate – a Lego plate with only one central stud (1×1 plates obviously excepted). These are used to facilitate half-stud offset building, while still staying legal.


KFOL – acronym for “Kid Fan (or Friend) of Lego” … actually the 5 to 12 demographic Lego was originally designed for.


LDD – Lego Digital Designer, a free software that allows enthusiasts to build Lego creations on a computer, using virtual bricks and pieces.

Legal Build – any creations that fall within the rules Lego has laid down for designing models in-house.

Lego Ideas – an official Lego programme were fans can present their (legal) MOCs, with a chance to see it produced as an official Lego model. Sets like Ghostbusters and Doctor Who started as Lego Ideas.

Legoland – Lego theme parks, currently open in Billund (Denmark, the original one), but also in Carlsbad (California), Dubai, Günzburg (Germany), Nusajaya (Malaysia), Windsor (United Kingdom), and Winter Haven (Florida). See more at the Legoland website.

LUG – acronym for “Lego User Group”, basically more-or-less formalised get-togethers where Lego fans meet on a more-or-less regular basis.


Microfigures – small figures used mainly in the Lego games series, and is some large creations that could not be achieved in Minifigure scale.

Midi Scale – a scale that is above the use of microfigures, but below the use of minifigures … mainly a Star Wars thing.

Mindstorms – Lego robot-building system, complete with electronics.

Minifigures – the well-known Lego figures with (usually) moveable head, arms and legs.

Minifigure Scale – basically any models that were built with minifigures in mind. Having said that, it is not a constant scale at all, but incorporates all models into which minifigures fit.

Mixels – a decidedly non-realistic interactive series of Lego sets that combine weird assortments of parts into creations straight out of the cheese-nightmares of animated movie designers. Colourful and fun.

MOC – acronym for “My Own Creation”, a model created from Lego, but without reference to instructions.


Nexo Knights – Lego interactive series announced in 2015, which seems to draw from medieval ind science-fiction influences.

Numbers – numbers used in Lego-speak refer to the number of studs on a brick or plate. A 1×1 would have only one stud (and is not a jumper plate). The iconic Lego brick would be the 2×8.


OOB – acronym for “Out of the Box” – as the designer intended.

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PAB – acronym for “Pick a Brick”, the supply of individual bricks by Lego either through their online store, or in a local Lego store (which will then have a “PAB Wall”).

Plates – basic Lego elements that are not as high as bricks, three plates on top of each other being as high as one brick. Connections are as for bricks, top and bottom.

POOP – acronym for “Parts Out of Other Parts”, generally referring to large, uninspiring pieces that could have been created by using standard bricks.

Printed Parts – any Lego bricks or pieces that have been printed in the factory, as opposed to those with stickers on them.

Purist – Lego fans who only use official Lego parts (and often only build legal). Purists can come up with brilliant problem solutions in their models, at other times they can bore you to death with reasons why “that cannot be done”.


SAH – also at times written as “[email protected]”, acronym for “Shop at Home” – the old name of the Lego online store.

Self-Reference – see Self-Reference.

Serious Play – Lego’s take on the ever-popular team-building exercise. To quote from the Lego website, it is “an innovative, experiential process designed to enhance innovation and business performance.”

Sigfig – a Lego minifigure used by a fan as his/her online identity, either in a signature or as an avatar.

SNOT – acronym for “Studs Not on Top” … and it is not what you might think, but a (legal) building technique that uses Lego sideways or upside-down.

STAMPS – acronym for “Stickers Across Multiple Pieces”, the worst idea ever.

Stickers – self-adhesive decorative elements Lego supplies for finishing a specific model. While their quality is generally good, the appearance is generally inferior to printed parts.


Technic – Lego series aimed at technically interested TFOLs and AFOLs, with often large and complicated (working) models representing actual technology.

TFOL – acronym for “Teen Fan (or Friend) of Lego”.

Tiles – Lego parts that have the same size as plates, but no studs on top. Used for creating smooth surfaces.


UCS – abbreviation for the “Ultimate Collectors’ Series”, sets that are larger in size than minifigure scale, and usually very expensive.


Vignette – a small scene that is created on a small plate, often involving minifigures.

VIP – Lego loyalty programme, shopping in Lego stores or the online shop earn you points, which translate into money-off vouchers.


WiP – as usual, this stands for “Work in Progress”, anything not yet (or possibly never) finished. Like the ultimate Lego model you want to build. Or this Lego Lexicon.

Do you have suggestions for our Lego lexicon? Leave comments below.

Read our little Lego lexicon for abbreviations and definitions