(Updated March 10, 2025) The matter of language mapping is not something for which there is often a need, but just in case, I’ll give a brief description here. So:

• You might have a situation where one, or both, languages (usually the target language) does not have an “engine” in the MT Cloud, but you would like to use a language (or even pair) which is similar enough, language-wise, that to use it (them) could be of benefit.
• Or you do have a TM for exactly that pair, but it might be useful to use also a neighbouring language in an MT engine.
• Or even that you do have an MT engine from another provider than LW but, again, looking at another language would be beneficial.

The mapping table in the Language Weaver (LW) Provider makes it possible for you to assign an MT engine (in LW) for a different language than the one in the project (or, in an exceptional case, both languages).

Let’s say – to use an actual case – I have a translation from English to Luxembourgish, which latter language does not figure as an MT language in Language Weaver. However, since Luxembourgish is not too far away from German, using an MT engine for En > De might be useful. But I don’t want to go back and change the actual project languages. Here is where the language mapping comes in. This is how to do it.

I select, as MT/TM provider, Language Weaver Provider and then Language Weaver Cloud. Luxembourgish is not offered as a target language by the Language Weaver Cloud, and therefore the En > Lu pair causes it to tell me that the Target (language) is “Not set”. To remedy that, and still in the LW Cloud dialog, I open the mapping table by clicking Open Language Mapping:

Here, Language is the language I want to use LW for, and Region denotes the language variants; together they make up my language selection in Studio, such as “English (United Kingdom)”, or “Arabic (Algeria)” and are denoted by the Trados code. I need to find the proper language selection for the language that I want to assign a TM engine to.

Now, what I am after is the Language code to assign to my Language, because that is what actually decides which MT engine Language Weaver is going to use. In this case I want Luxembourgish to be mapped onto German, so I search for “lux” (in fact I only need to type “lu”; also note that the search filter looks at both Language and Region), and in the row for the Luxembourgish language (it only has one Region) I enter the Language code for German, “ger”, and click Apply. Getting back to the LW Cloud dialogue, I now see this:

The language pair is the same, but the target language for LW Cloud is now set to German (no longer “Not set”) – exactly as I wanted.

If the language to which I am mapping is a more obscure one for which I cannot easily find the language code in this table, I click the option Missing a language code? at the bottom of the table. Then I arrive at a Language Codes list: the available languages and their codes. (Actually practically all languages for which there is a language code is already in the Language Weaver Provider list; where one is missing it is probably not in the Language Codes list.)

If my project’s target language already has its own MT engine but I want to look at another (related) language, I can do such a mapping here. Let’s say I translate to Danish but would be helped by looking at an MT engine for Norwegian as the target. In the mapping table I select Danish – Danish and change the MT code “dan” into “nor”, click Apply, and get the desired result.

So – in principle simple although it takes a bit of text to explain it. My thanks to the ever-patient Paul Filkin for taking his time to clarify all my confusion.