Dysprosium oxide (Dy<sub>2</sub>O<sub>3</sub>) is a sesquioxide compound of the rare earth metal dysprosium. It is a pastel yellowish-greenish, slightly hygroscopic powder having specialized uses in ceramics, glass, phosphors, lasers, dysprosium metal halide lamps, and as a Faraday rotator.
It can react with acids to produce the corresponding dysprosium(III) salts: