A glossary can be… should be… far more than just a word list for looking things up in. A glossary can do all of the following for you…
You might also want to have a look at the page How to build a glossary?
1. Learning about stuff
In reading your documents and looking up terminology (looking up definitions rather than just translations as explained in How to build a glossary? ) you are learning (understanding) a little bit more about how the technical field (and the world) works. This is more valuable than learning only the translations of words.
2. Activation
Adding to a glossary creates repeated exposure to the same terms, this helps you learn them and activate them (see Gile’s gravitational model of language acquisition).
You can even create extra repetition steps to enhance activation. For example, if you prepare from documents you might look up terms and note what you find on the document itself FIRST and then later come back to it to transfer the terms to a word-list for the meeting (or your glossary itself).
Just before the meeting, or even your interpreting turn starts, you can test yourself from the word-list to activate them for use on microphone.
3. Looking things up while working
Yes, some interpreters manage to search through a glossary while interpreting simultaneously. However, the overwhelming majority rely on activation prior to working rather than looking things up while working.
More common is to check what you, or your colleague, has just heard immediately afterwards.
4. Long-term memory
If you write up your notes AFTER the meeting you are creating a further repetition step that will anchor the terms in a longer-term memory.
5. Preparation for next time
A well-built glossary will help you prepare for the next time you work for this same meeting, or in the same technical field.
See also Setton & Dawrant p341 & Gillies (Reasons not to automate glossary building)
by Andy Gillies