Hmmm, interesting! I though it would be especially interesting to to countries where English is not so popular. I’d expect users in such countries would want that almost as much (or more) as translated forum UI.
For example, tag
#hiking is in English. In Croatian it would be
#planinarenje (and in Korean translation claims it would be
#등산 - hopefully that is correct).
Thus, when Croatian user (who does not know English) types
planinarenje in search box, if language synonyms are implemented, they would be shown all posts tagged with
hiking. Same with Korean user typing
등산 as a search term.
I think it would be quite useful for people not familiar with English. Don’t you @adreamy think so? (and if not, why not?)
But I think implementing it would take more than a forum post with people writing their suggestions for synonyms there. Because there are new values appearing from time to time, and they should be added too, and without some translation-specific UI it would be hard to be notified and keep it updated.
The problem with idea of just increasing the number of tags and dual-tagging (e.g. adding both
#planinarenje in example above) is that it is only available in small subset of languages that original poster speaks (e.g. in my case I could add tags in Croatian and English only, I can’t add Polish or Korean or German or other languages), and of course even bigger problem that only the original poster can set tags.
So while Korean users will be able to find your posts @adreamy by using tags in Korean, they wouldn’t be able to find my posts about same tag in Croatian (even if they could read them via translation if they could find them).
Thus I think the synonyms idea sounds very interesting, if there are people willing to translate (at least most popular hundred or so) tags.