Wiktionary is a multilingual, web-based project to create a free content dictionary of all words in all languages. Developed by Wikimedia Foundation
License: Open Source
Wiktionary offers a vast, collaboratively edited resource that includes rich etymological information and audio pronunciations, while Google Dictionary provides a more streamlined and user-friendly experience, integrated with Google services for quick access. Wiktionary excels in depth and multilingual support, whereas Google Dictionary is better for users seeking fast, reliable definitions.