PYD or pyd may refer to: "PYD" (song), a 2013 single by Justin Bieber. Democratic Union Party (Syria) (Partiya Yekîtiya Demokrat), a Kurdish Syrian political party. Pyrin domain (PYD), or the protein domain. Positive youth development. .pyd, a file extension for the Python programming language. Pyramid railway station, Australia https://en.wikipedia.org/wiki/PYD