| Acronym | Definition |
|---|
| ARJ | Arch Chemicals, Inc. (stock symbol) |
| ARJ | Compressed file extension (archiving program by Robert K. Jung) |
| ARJ | Archive File |
| ARJ | Avro Regional Jet |
| ARJ | American Radio Journal (Lincoln Institute of Public Opinion Research, Inc; Harrisburg, PA) |
| ARJ | Acquisition Review Journal (Defense Acquisition University) |
| ARJ | Answers Research Journal (interdisciplinary technical journal) |
| ARJ | Admission Reject |
| ARJ | Association des Radios Juives (French: Association of Jewish Radio; est. 1999; France and Belgium) |
| ARJ | Agglomération Riomoise pour la Jeunesse (French youth agglomeration) |