How to use a glossary (or term base) in your translation project
This feature is available on all account tiers (including the free plan) but note that a glossary project contributes to your quota usage.
Creating a glossary / managing terms
Loco glossaries are just translation projects like any other. To add new terms, simply create a new project for your glossary, and start adding common words and short phrases. Translate these into as many languages as needed.
There's nothing special about a glossary project. It's a translation project like any other. However, it's advisable to maintain your terminology using separate assets for single words or very short phrases. Consider tagging your assets with the most relevant part of speech (e.g "Noun") and use the context or notes for further disambiguation.
Tip: Loco can import various file formats suitable for glossaries, including CSV and TBX files.
Adding glossaries as term bases for other projects
Once a glossary is created, you can make its terms available to other projects via those projects' settings.
For example, you may have a project called "Jargon" (containing short phrases) and another called "Company website" (containing longer texts). From the "Company website" project settings, select the "Sources" tab and choose "Jargon" from the Glossaries dropdown list.

Multi-language glossaries
A single project can be used as a multi-directional glossary for all your translation languages. For example: A glossary containing English, French and German can be searched for English→French, French→English, German→French, and so on.
It's also possible to maintain multiple bi-directional glossaries. This can be useful if the set of terms need to be different, or if you have other metadata (like tags) that differ across languages. For example, by maintaining two term bases ("French→English", and "German→English") you can add them both as glossaries to a third project and look up terms in all three languages.
Accessing terms during translation
Once a project has a glossary attached, you can browse its terms while you translate longer segments of text. Loco will automatically scan the source text for any matching terms.
Matching terms are highlighted in the Sources pane of the editor. Clicking a highlighted term will show more detail, including translations for the current language being edited.

Machine translation
Separately from adding glossary sources to projects, Loco can expose glossary terms to its translator bots. Specifically this is available for DeepL, and AI prompt-based translator bots.
For DeepL, the entire project is synchronized to a DeepL glossary, whereas prompt-based translation is performed more like the user interface shown above, whereby only relevant terms are sent along with the source text.
Loco will find word variations, but not synonyms. For example: the terms "jump", and "jumps" would also match "jumped", but not "leaped" or "hopped". A term's context is not considered when matching, but will be sent with the source text. LLMs are left to decide whether to use terms in mismatching contexts.
Currently one glossary project is selected per bot configuration. It will be used regardless of the project is being translated, so be warned that a glossary can end up being used to translate itself. It's on the roadmap to use the project's configured glossary as an alternative to the bot's configured one.