UUN

UUN, Uun, or uun can refer to:


 * Urine urea nitrogen, a medical test that measures urea in urine
 * Another name for darmstadtium, a transactinide chemical element
 * Baruun-Urt Airport, an airport located in Baruun-Urt, Mongolia, by IATA code
 * Pazeh language, an extinct language formerly spoken in Taiwan, by ISO 639 code
 * "Universal User Name"; see List of computing and IT abbreviations