Il Nuovo De Mauro
Tullio De Mauro's dictionary, free on Internazionale — with frequency labels.
DictionariesFreeIntermediateAdvancedB1–C2
What it actually is
About 160,000 entries, and uniquely useful for learners because De Mauro tags words by frequency band (fondamentale, di alto uso, comune…), so you can see at a glance whether a word is worth learning. Definitions are plainer than Treccani's, which makes it the friendlier first monolingual dictionary. Completely free and ad-supported; the interface is dated and there is no app.
What it covers
- Vocabulary
- Reading