Implement a button that copies definitions from dictionaries.
If you want to look up a word, you have to copy and paste, which takes a long time. It would be better to automate that.
Why not create a main dictionary that already shows all that information, like Yomichan or Language Reactor does? With a single click, you can save the word without having to copy and paste.
This would be really nice, but it is not feasible. I'm not sure what LR or Yomichan does :-)
First, Lute users have various native languages (English, Spanish, Portuguese, French ....) and they can study different languages. A "central dictionary" would need to support each possible combination of L1-L2 languages. So with 10 languages, that's 100 dictionaries.
Second, there are different dictionaries, of varying quality, for languages. For Spanish, sometimes it's best to look at an English only dictionary. More advanced people prefer monolingual dictionaries. Each dictionary has their own layout, markup, etc. If Lute tried to "skin" those dicts so they could be easily handled, which creates work for each dictionary.
It's not possible, as far as I know, to have a single reliable way to parse the hundreds of dictionaries and extract information ... at least no way that I know of. Corrections welcomed.
LingQ does "crowdsourced" user definitions. That's kind of nice, and also not nice, as those definitions are often quite basic, or just incomplete. e.g. the verb "quedar" in Spanish has dozens of meanings and usages, and can't be described as a single word.
I'm not sure how Lute's dictionaries could be improved. And actually, when I wrote Lute, I wanted to have to work to create the definition, because that's part of the learning process. For simpler things, you could do a bulk load of terms and definitions into your db. I know it's not what some people would want, but I couldn't see a reasonable way to do what you suggest here.