What a subtitle glossary is
A glossary is a shared list of words and phrases that should be handled the same way every time they appear. In a subtitle project, it usually records how to spell people’s names, how to write product or place names, which specialist words are used and, for translated work, which target-language term has been approved for each source term.
The value is consistency. Without a glossary, one person may write “e-mail” and another “email,” or one subtitler may translate a recurring job title three different ways across a series. Viewers notice these inconsistencies even when they cannot say why a file feels careless, and a changing term can be confusing if it looks like a different thing.
When a glossary is worth the effort
A single short video made by one person may not need a formal list. A glossary starts to pay off when any of these is true:
- Several people are writing or reviewing subtitles.
- The material is a series or has many episodes or modules.
- The content contains specialist vocabulary, such as medical terminology, legal terms or technical product language.
- The subtitles will be translated into more than one language, as in multilingual projects.
- The same material may be revised or reused later.
Even for small jobs, a few lines of notes about unusual names can save time at the review stage.
What to put in it
A useful glossary is short enough to be checked quickly and detailed enough to settle real questions. Common columns include:
- Term as spoken or written in the source. The exact form people use.
- Approved form in the subtitles. The spelling, capitalization and any hyphenation.
- Notes. For example, “always capitalized,” “do not translate,” or “refers to the company, not the product.”
- Approved translation per language. Added one column per target language.
- Source of the decision. Who confirmed it, such as the client, the subject expert or the project lead.
- Pronunciation or alternative spellings. Helpful when speakers say a name differently from how it is written.
Categories worth thinking about include people’s names and titles, organizations, place names, product and feature names, acronyms and abbreviations, recurring phrases or slogans, and words that should stay untranslated. For a subtitle project, it also helps to note preferences that are not strictly terms, such as how to write numbers in a particular context, although general rules on number formatting usually belong in the style guide instead.
Building the first version
The best time to start is before the first subtitle is written. Two sources are especially useful.
First, any material supplied with the video: a script, slides, a product sheet, a website, a cast or speaker list. These often contain the correct spellings of names and terms.
Second, a quick listen or read-through of the content itself. Someone who has watched the video can note names and unusual words as they come up. If the first draft of the text comes from automated transcription, scanning that draft for words that look wrong is a fast way to find terms to add. The same list can then feed a custom vocabulary setting in the tool, where one is available, although how well that works varies from tool to tool.
Avoid trying to make the list complete on day one. A glossary that is too long gets ignored. Start with the terms most likely to be misspelled or disputed, then add as the work reveals new ones.
Keeping it consistent across languages
For translated subtitles, a glossary becomes the contract between the source team and each translator. If the source says “the Foundation,” the list should state how that is rendered in each language, or whether the original is kept. Without that, two translators working on different episodes may choose different renderings.
Translators may disagree with an approved term, and that is useful. If a glossary entry sounds unnatural in a language, the right response is to raise it with the project owner so the entry can be changed for everyone, rather than for one file to quietly diverge. Many teams pair the glossary with a translation memory, which stores previously approved sentences so that repeated lines are rendered the same way, but the two serve different purposes: a glossary governs terms, while the memory governs sentences.
Who owns it
Every glossary needs one owner who approves changes. That might be a project coordinator, a lead reviewer or a client contact. Without an owner, entries pile up with conflicting spellings.
Practical habits that help:
- Keep one current version in a place everyone can reach, and treat older copies as obsolete. This is the same principle as good version control for the subtitle files themselves.
- Date changes and note why they were made.
- When a term changes, check earlier files that used the old form.
- Share updates with everyone, not just the person who asked.
Using it during review
A glossary is only useful if someone checks against it. During proofreading, a reviewer can search each file for the key terms and confirm the spelling. Searching for known wrong variants, such as an old name or a common misspelling, is an effective way to catch leftovers. Names and specialist words are the most common trouble spots, so even a quick search pass is worthwhile.
For high-stakes material, such as medical or legal content, a glossary does not replace review by a qualified person. It reduces inconsistency but cannot confirm that a term is right in context.
Keep it practical
A good glossary is plain, current and easy to open. It should answer questions quickly: how do we spell this, and what do we do with it? If the team stops using it, the likely causes are that it is too long, out of date or hard to find. Trim it, update it and make it easy to reach, and it will keep paying off through the life of the project.