Posted in Aviation, Government & Military, Information Technology, Organizations, Science DUN stands for Dial-Up Networking DUN stands for Dunsmuir (Amtrak station code; Dunsmuir, CA) DUN stands for Dewan Undangan Negeri (Malay: State Legislative Assembly) DUN stands for Derelict, Underused and Neglected (land; UK) DUN stands for Danske Unge Naturister (Danish: Danish Young Naturist)