Federico, as indicated by the classification as "experimental" [1], the definition end point [2] is at a very early point of its development. The mobile app team has added preliminary support for extracting definitions in the content service [3] using Parsoid's template metadata, and is using this end point to power a "define this word" feature in the next version of the Android app. You can preview the feature in the beta Android app when browsing English Wikipedia by selecting a word, and then hitting the 'definition' icon next to 'copy'. In this first iteration, only English Wiktionary is supported. Generalizing the service and API end point to provide definitions using more or all Wiktionaries will require more work and planning. In the next iteration, I would expect a focus on enabling collaborative definition and maintenance of extraction rules, as well as broader involvement of Wiktionary communities in the planning process. The timing for the next iteration depends partly on the mobile app team's priorities, so I will defer to the team to comment on this. To summarize: We are aiming to gradually develop this into a generally useful, stable and well-documented API entry point for word definitions. The experimental end point published right now is just the beginning, and you are very much invited to help shape the way forward. Gabriel [1]: https://www.mediawiki.org/wiki/API_versioning#Experimental [2]: https://en.wiktionary.org/api/rest_v1/?doc#!/Page_content/get_page_definiti… [3]: https://github.com/wikimedia/mediawiki-services-mobileapps/blob/master/lib/… -- Gabriel Wicke Principal Engineer, Wikimedia Foundation