Largest open-source dictionary w/ brief definitions (not wiktionary) [closed]

Solution 1:

You may be looking for WordNet, a lexical database for English developed by Princeton's Computer Science department. It has a permissive license allowing free use even in commercial applications. However, WordNet does not have “closed-class” words, including pronouns, prepositions, conjunctions, determiners, and particles.

Solution 2:

The moreofit web site can be a good start to find sites similar to, here, wiktionary:

www.moreofit.com/similar-to/en.wiktionary.org/Top_10_Sites_Like_Wiktionary_En

The result includes dict.org, which can be of interest considering what you are after.

Solution 3:

I agree that WordNet is a pretty good source for definitions. I have started to build a multilingual dictionary (Deect) on top of WordNet's English words and definitions (actually included a few more things), and the users usually like the definitions from WordNet.