Create a data glossary

Define and share key terms across your organisation so data is clear and consistent

A data glossary is a simple list of your organisation’s key data terms and what they mean.

It's like a small dictionary. It helps everyone stay aligned across all areas of the business. 

Why a data glossary matters for AI

AI tools learn patterns from data. If people use the same term in different ways, your data can quickly become confusing and inconsistent.

Common terms – like customer, order, supplier and transaction – can mean different things across your organisation. Without clear definitions, this can lead to:

  • reports that don’t match
  • key measures that are hard to compare
  • decisions taking longer
  • less trust in your data.

A data glossary helps people use key terms in the same way so AI tools and systems can use your data more consistently.

A data glossary also improves:

  • data literacy – people understand the data they use
  • data governance – terms are agreed, owned and kept up to date
  • trust in insights – reports match and people make decisions using the same numbers
  • AI readiness – AI tools work better with consistent, high-quality data. 

How to create a data glossary

You don’t need a large project to get started. Start small and build it over time.

Step 1: Pick the most important terms

Choose key terms that your organisation uses often. Start with terms linked to money, customers, staff, stock or delivery. For example:

  • customer
  • order
  • invoice
  • refund
  • supplier
  • product
  • staff member.

Step 2: Write a simple definition for each term

Keep each definition short and avoid technical language.

If a term is hard to explain, that may be a sign your organisation isn’t using it consistently yet.

Step 3: Add rules and examples

Add a brief note about what the term includes and doesn’t include. Examples help people apply the definition in real work.

Step 4: Assign an owner

Pick one person or team to keep definitions up to date. This doesn’t need to be a data expert – just someone who understands the business meaning.

Step 5: Put it somewhere easy to find

Use a shared document, spreadsheet or wiki page. Make sure people across your organisation can find the glossary and suggest updates. 

What to include in a data glossary

A basic data glossary can include the following information:

  • Term – the official name used across the organisation.
  • Definition – a simple, clear definition for non‑technical users.
  • Location – where the term appears across the organisation.
  • Alternative terms – similar words for the term that people can refer to.
  • Scope – what the term does and doesn’t include.
  • Examples – what the term means in practice.
  • Related terms – connected terms in the glossary.
  • Owner – who is accountable for the definition and keeping it up to date.
  • Priority – high, medium or low based on where to focus your data quality effort first.

Keep it up to date

A glossary only works if people use it. These small habits help:

  • Review your top terms every 3 to 6 months.
  • Update definitions when systems or processes change.
  • Add new terms when you add new products, services or software.
  • Ask staff to flag terms that cause confusion.