SIV and Siv may refer to: Simian immunodeficiency virus, a virus found in primates and related to HIV Siv, a character in the children's fiction book series Guardians of Ga'Hoole SIV, the IATA and FAA airport code for Sullivan County Airport, Sullivan County, Indiana, USA Statens Invandrarverket, the former name of Swedish immigration authority (on Swedish Wikipedia) Stress-induced voiding, a failure mechanism in MOSFETs Structured investment vehicle, a type of fund in the shadow banking s… (More on Siv)