| Acronym | Definition |
|---|
| MRO | Maintenance, Repair and Overhaul |
| MRO | Medical Review Officer (test result interpretation) |
| MRO | Mars Reconnaissance Orbiter |
| MRO | Mauritanian Ouguiya (ISO currency code) |
| MRO | Marathon Oil Corporation (stock symbol) |
| MRO | Murchison Radio-Astronomy Observatory (Australia) |
| MRO | Motorcycle Rights Organization |
| MRO | Midwest Reliability Organization (Roseville, MN) |
| MRO | Method Resolution Order (Python programming language) |
| MRO | Maintenance Repair Organization (aircraft) |
| MRO | Maintenance, Repair & Operations |
| MRO | Machine Repair Option |
| MRO | Multi Region Option |
| MRO | Memory Read Out |
| MRO | Maintenance Repair and Operating |
| MRO | Multi Region Operation |
| MRO | Market Research Online |
| MRO | Mad River Outfitters (Columbus, OH) |
| MRO | Mountains and Rivers Order (Zen Buddhism) |
| MRO | Motor Racing Outreach (ministry for NASCAR drivers & crews) |
| MRO | Market Research Organization (various locations) |
| MRO | Magdalena Ridge Observatory |
| MRO | Mandal Revenue Officer (India) |
| MRO | Mobile Repayment Option |
| MRO | Medical Records Online (King of Prussia, PA) |
| MRO | Midwest Regional Office (Illinois) |
| MRO | Materiel Release Order |
| MRO | Material Release Order |
| MRO | Mission Radio Operator |
| MRO | Main Refinancing Operation (European Central Bank) |
| MRO | Maximum-Random Overlap (meteorology) |
| MRO | Memory Readout (US NASA) |
| MRO | Medical Review Official |
| MRO | Mini Racing Online (computer game) |
| MRO | Men's Rights Online (website) |
| MRO | Mandatory Removal Offense (US) |
| MRO | Melbourne Research Office (University of Melbourne; Melbourne, Australia) |
| MRO | Medical Regulating Office(r) |
| MRO | Ministry Records Officer (Canada) |
| MRO | Maintenance Repair Order |
| MRO | Marine Reported On (US DoD) |
| MRO | Manufacturer's Representative Organization |
| MRO | Manchester Recorder Orchestra (Manchester, England) |
| MRO | Material Related Overhead |
| MRO | Monster Ranch Online (gaming) |
| MRO | Mentally Retarded Offender (law enforcement) |
| MRO | Materials Requisition Order |
| MRO | Manhattan Recorder Orchestra (New York) |
| MRO | Mendip Rescue Organisation (UK) |
| MRO | Maintenance, Repair & Operating/Operations |
| MRO | Machine Repair Operation |
| MRO | Motor Route Order Number |
| MRO | Military Response Option |
| MRO | Message Releasing Officer |
| MRO | Medical Readiness Officer |
| MRO | Multiresistant Organism |
| MRO | Movement Report Officer |
| MRO | Monthly Routine Order |
| MRO | Multi-Region Operation/Option |
| MRO | Maintenance, Repair and Office Supply |
| MRO | Mid-Range Objective |