***Meaning*** :: <u>O</u>ff-<u>R</u>oute <u>O</u>bstruction <u>C</u>learance <u>A</u>ltitude ***Additional Info***: An off-route obstruction clearance altitude (OROCA) is an off-route altitude that provides obstruction clearance with a 1,000-foot buffer in non-mountainous terrain areas and a 2,000-foot buffer in designated mountainous areas within the United States. https://www.faa.gov/air_traffic/flight_info/aeronav/acf/media/Presentations/17-02-RD316_AOPA_OROCA.pdf #acronym