LEGO Basics & Terminology Explained

Understanding LEGO Terms, Meanings, and Core Concepts

LEGO is more than just a brand name. Over time, it has developed its own language, terminology, and concepts that are often confusing to newcomers and even long-time fans.

This page explains what LEGO means, common LEGO terms, and basic concepts used by fans and the LEGO community — without buying advice, product recommendations, or display guidance.

It is part of the LEGO Knowledge Hub, which brings together essential LEGO concepts, terminology, and care information.

What Does “LEGO” Mean?

The name LEGO comes from the Danish phrase “leg godt”, which means “play well.”

LEGO was founded in Denmark, and the name reflects the brand’s original philosophy: encouraging creativity, imagination, and quality play.
Despite common assumptions, the word “LEGO” is not an acronym.

Is LEGO Singular or Plural?

A frequent point of confusion is whether “LEGO” should be plural.

Correct usage: LEGO bricks, LEGO sets

Incorrect usage: legos

LEGO is treated as an adjective, not a noun. While “legos” is widely used informally, it is not grammatically correct according to LEGO’s official language guidelines.

What Is “Adult LEGO”?

You may hear people refer to “adult LEGO,” especially when discussing complex builds or collectors.

“Adult LEGO” generally refers to:

LEGO enjoyed by adults rather than children

More complex or time-intensive builds

LEGO as a hobby, not just a toy

There is no official category called “adult LEGO” — it is a community term rather than a formal product classification.

The broader role of adults within the LEGO community is explored in LEGO Age, Fans & Culture.

What Does AFOL Mean?

AFOL stands for Adult Fan of LEGO.

This term is commonly used within the LEGO community to describe adults who actively build, collect, or engage with LEGO as a hobby.
Similar community terms include:

TFOL – Teen Fan of LEGO

KFOL – Kid Fan of LEGO

These terms are informal and primarily used in fan discussions.

What Is a LEGO Set vs LEGO Pieces?

Understanding the difference between sets and pieces helps clarify many LEGO discussions.

LEGO sets are boxed products designed around a specific build

LEGO pieces (or elements) are the individual bricks and parts used to build

Once a set is opened, its pieces can be reused freely — LEGO is designed as a system rather than a one-time build.

What Does “MOC” Mean in LEGO?

MOC stands for My Own Creation.

It refers to LEGO builds designed by fans rather than official LEGO designers.
MOCs can range from small custom models to large, highly detailed builds and are a major part of LEGO fan culture.

What Is Clutch Power?

Clutch power describes how firmly LEGO bricks connect to each other.

It is a key design principle that balances:

Bricks staying together securely

Bricks being easy to separate without damage

Consistent clutch power is one reason LEGO bricks remain compatible across decades.

Are All LEGO Bricks the Same Size?

Standard LEGO bricks follow a consistent sizing system, which allows pieces from different years and themes to work together.

While LEGO produces many specialised elements, core dimensions remain standardised.
This consistency is central to LEGO’s long-term usability and system design.

Common LEGO Terminology Explained

Here are a few frequently used LEGO terms:

Element – An individual LEGO part

Stud – The round bumps on top of bricks

Plate – A flatter LEGO piece, thinner than a brick

Tile – A smooth LEGO piece without studs

Technic – LEGO elements designed for mechanical functions

Understanding these terms helps make sense of instructions, discussions, and fan content.

Why LEGO Terminology Matters

LEGO terminology exists to describe how a flexible building system works.
Knowing these terms helps builders communicate ideas, follow instructions, and participate in LEGO communities more easily.

Final Thoughts

LEGO has its own vocabulary because it functions as a system, not just a collection of toys.
Understanding basic LEGO terms and concepts makes it easier to explore more advanced builds, fan culture, and long-term collecting.

If you’re exploring how LEGO sets are displayed and protected, see our guide to LEGO display methods.