ISAR may refer to: Intergovernmental Working Group of Experts on International Standards of Accounting and Reporting International Search and Rescue Competition Institute for the Study of Academic Racism Inverse synthetic aperture radar, a technique to generate two-dimensional radar images of a target Intelligible semi-automated reasoning, the formal proof language of the Isabelle proof assistant See also Isar, a German river Isar, Province of Burgos, a municipality located in Castile and León, Spain Isar Rural District, in Iran