Integrate a synonym or similar ideas dictionary

[Masclins]

Description of the current behaviour
We used to use Open Thesaurus in catalan. But their API and website is no longer available.
Therefore we cannot offer users similar words when their search is missing (or simply to give some suggestions)

Description of the behaviour you'd like
We'd need to find a new dictionary and use it.
It could be either an external API, or we could create a service for it on our server.

Description of considered alternatives
An alternative would be to simply not include this feature.
It's not necessary, but it really improves the Signepedia.

[Masclins]

Apparently their API is up again, but still we should need to build it ourselves.
https://github.com/Softcatala/openthesaurus