The Finnish Wiktionary
Free, multilingual dictionary

The Finnish Wiktionary has nearly 450,000 articles. In addition to translations in different languages, the page contains information about the meaning of the word, synonyms, related words, pronunciation, inflection forms, word type, word class, the origin of the word, and the presence of the word in idioms. Authors: volunteers

Pros
large and extensive content
Comprehensive and versatile information about the entries
multilingual
free
Cons
translations may contain errors