What’s a LEGO glossary good for anyway?

Well, the world of LEGO is wide, diverse and rich in history. It’s also rich in hobby specific terms and concepts and that can confuse newcomers.

This LEGO glossary, of key terms, facts and figures, might help you navigate the wonders of the LEGO universe. It will grow over time, so if you have suggestions about terms you think should be added, let me know in the comments section below!


# | A | B | C | D | E | F | G | H | I | K | L | M | P | R | S | T | U | V


A very special number for all LEGO lovers. This is the year Ole Kirk Christiansen founded the company which has grown in to the world’s favourite brick supplier!


Acrylonitrile Butadiene Styrene is the thermoplastic polymer (plastic) used by LEGO to create their interlocking brick system elements since 1958. Fun fact: The LEGO Group has committed $150 million USD to developing new, sustainable alternatives to ABS by the year 2030.

I’m an AFOL. You may be an AFOL too. Simply put, an AFOL is an “Adult Fan of LEGO”.


Brick Built
LEGO objects that are “brick built” are comprised of many smaller pieces, rather than being one single, moulded element. Example: Rather than using a single, pre-made door element, a designer might choose to build a door using a number of smaller pieces. Capiche?

The common name for a completed LEGO set or creation. As in “Phwoah, that’s a nice build!”


Clutch power
Pick up any two pieces of LEGO produced since 1958 and stick them together and you’ll observe “clutch power” in the wild. This term describes the perfect amount of “stickiness” that LEGO has designed which means pieces stay together when assembled, but come apart when desired. Clutch Power is also a point system used on the popular LEGO Ideas system. The higher a member’s Clutch Power, the more they have contributed to that specific online community.

The original name for the LEGO Ideas crowdsourcing program. Cuusoo, a Japanese word, means to wonder about something that does not yet exist.


Dark Ages
Dark Ages are those years between childhood and the rediscovery of the joys of LEGO as an adult. (For me, the Dark Ages were between the ages of 13 and 21 :()

Design ID
Design IDs are the tiny reference numbers marked on each LEGO element, signifying the mould used to shape that piece.

The oversized LEGO brick system designed for little hands, aged 1 1/2 to 5. Impressively, the larger DUPLO elements interlock with their smaller cousins – a testament to the ingenious engineering which means that each LEGO part is compatible with all others.


Element (and Element IDs)
The official word for describing each item in the LEGO parts library. While Design IDs reference only the shape of a part, an Element ID references both shape and colour.

Erling Brick
Named after its designer (Erling Dideriksen) this SNOT element was introduced in 1979 and has become a staple for every serious LEGO builder. You can see an example of an Erling Brick in the Brick Set library, here.


This specific LEGO theme earns a place in this glossary for a few reasons. The Friends theme, introduced in 2012, has been a raging success for The LEGO Group, becoming the companies principal offering for young female consumers. (Of course, in an ideal world, gender would probably be left out of set designs altogether) The Friends theme is also significant as it introduced the minidoll – a new human figure design to the LEGO universe.

A little like FOMO (a fear of missing out) this term describes the Fear of Missing LEGO we experience from time to time, rummaging around in piles of LEGO for a brick we just can’t find (but must be here, surely?!)


Like (and sounds like) AFOL, GayFOLs are adult fans of LEGO who are also members of the LGBTQI+ community. The term is broadly applicable to anyone who identifies as a member of or as allied with this community of people. See this GayFOL group on Facebook.

Greebles (also greeblies or greebling)
A word for describing the small elements and details added to the surfaces of LEGO creations. Greebles aren’t functional, rather they only increase aesthetic appeal. Often used in sci-fi creations to suggest technical/mechanical details (e.g. the ridiculously amazing level of detail covering the hull of the UCS Millennium Falcon.)


Half-Stud Offset
An advanced building technique that allows the placement of elements in a fashion which ignores the standard alignment of LEGO pieces.


The LEGO Ideas program (formerly LEGO Cuusoo) is the LEGO Group’s design crowdsourcing platform, allowing amateur builders the chance to submit ideas for possible production. The Ideas program has given us a number of excellent, fan-designed projects including models based on film and TV icons (like Back to the Future and Doctor Who) as well as original concepts (like LEGO Birds and a Labyrinth Marble Maze. You can explore new LEGO Ideas projects here.


Like an AFOL, a KFOL is a Kid Fan of LEGO. (Not a kid anymore but not quite an adult? You might be a TFOL – a Teen Fan of LEGO.)


The LAN is the LEGO Ambassadors Network – the LEGO Groups AFOL community outreach program. The LAN is compromised of representatives of RLUGs and RLFM.

Lego Digital Designer is a software program developed by the LEGO Group, used for creating virtual builds and instruction sets. You can learn more about LDD and download programs for Windows and OS X here.

LEGO House
The visitor discovery centre in Billund, Denmark, LEGO House has been designed by Bjarke Ingels’ architecture firm BIG to resemble a stack of LEGO bricks. Awesome!

A number of LEGOLAND theme parks have sprung up around the world since the LEGO Group first opened the doors of the original site in Billund in 1968. Once operated by LEGO directly, the parks are now operated under a licence issued to Merlin Entertainments.

Nope. Uh-uh. Just no. In the case of LEGO, the singular is also the plural. Just like sheep, fish, folk and deer. You can have one LEGO brick and you can have many LEGO bricks. Easy!

Licenced Theme
The first LEGO Theme based on the third-party intellectual property (IP) of another company was the Star Wars theme, which started in 1999 and continues on to this day. When LEGO creates models based on the IP of other companies, it must pay a licence fee (usually resulting in higher retail prices for customers for those products.)


Single LEGO elements which represent small figures. Often used in builds to represent trophies or in microscale builds as humans.

The scale for builds in which a minifig would appear too large if used to represent a human. Essentially, any builds that are smaller than minifig scale.

Introduced with the Friends theme in 2012, the minidoll is a new style of minifig scale human figure, now also used in the LEGO Elves and Disney Princess themes.

The name for the little folk who have appeared in LEGO sets since their introduction in 1978. Patented to the LEGO Group, minifigs are often highly collectible – so much so that they have inspired a Collectable Minifigure Series.

Miniland was first the name of the popular “tiny town” attractions created for each LEGOLAND and now also a way of classifying builds that adhere to the specific scale rations used in minilands.

Short for “My Own Creation” and a descriptor of essential anything you create with LEGO without following an instruction sheet.

A style of build, usually architectural, that allows for discrete builds to be connected and configured next to one another to arrange larger scenes. In recent years, LEGO has created a range of modular buildings that are wildly popular among AFOLs.


“Parting out”
The process of sorting a LEGO set in to groups of similar elements, with the view to using these elements in other projects or builds, rather than completing the suggested model.

Plates (and baseplates)
Plates are one third the thickness (height) of standard LEGO bricks and come in a range of widths and lengths. Not be confused with baseplates which are usually the same thickness (height) but much, much bigger in terms of width and length. Baseplates are often used for landscaping and as the starting point for larger builds and dioramas.

The plastic bags LEGO uses to package small sets. Most commonly used for promotional and giveaway sets.


These acronyms stand for Recognised LEGO User Group and Recognised Lego Fan Media. The latter is a designation given to fan media outlets which have demonstrated excellence in their coverage of, and commitment to raising the profile of, the world of LEGO.


A SigFig, or signature minifig, is the name for the avatars AFOLS often use for their online presence, using LEGO minifigure likeness (sometimes accurate, sometimes aspirational) to represent themselves.

An abbreviation of “Studs Not on Top”, SNOT is a building style that results in the studs on LEGO studs facing downwards, sideways… in fact anyway but up! It’s also just fun to say. SNOT!

When great care is taken to conceal all visible studs in a build, usually through a combination of SNOT methods and the use of plates, a build my appear to be “studless”.

A characteristic of many LEGO builds, swooshability describes the ability to pick up a model and literally “swoosh” it around in the air as one might do with a toy plane.


The Technic system came along in 1977, offering a range of new elements (like rods, axles, gears, and eventually hydraulic and motor systems) that allow for the construction of moving, functional objects. Popular with educators and AFOLs alike.

LEGO Themes are the named categories of products which share common design language and play appeal (e.g. Pirates, City, Friends) or relate to specific licensed brands (e.g. Indiana Jones, Harry Potter, Batman.) The first Themes, Town, Castle and Space, were introduced way back in 1978!

Just like a plate, but smooth on top.

The LEGO Group (of companies) is the parent company which oversees all LEGO operations and brands worldwide.


The Ultimate Collector Series is a range of complicated, high part-count sets designed for AFOLs and older, more experienced builders. The first UCS product, the TIE Interceptor (7181), released in the year 2000.


A popular MOC format, vignettes presented small scenes, often composed with isometric perspective including two background planes and a “floor”. Usually depicting a “slice” of a greater scene or concept, great vignettes feature excellent and refined part selections and showcase the builder’s eye for compact detail and storytelling. These wonderful Harry Potter vignettes are a great example of the format.

Build a better LEGO Glossary!

Are there terms missing from this list that you’d like to see added? Is anything unclear? Do you have great examples of some of the concepts or facts that you’d like to share? Jot your reply below!