| Acronym | Definition |
|---|
| JAR | Just a Reminder |
| JAR | Java Archive |
| JAR | Just about Right |
| JAR | Journal of Automated Reasoning |
| JAR | Japan Association for Refugees |
| JAR | Joint Aviation Requirements |
| JAR | Jewish Autonomous Region (Russian Federation) |
| JAR | Journal of Anthropological Research (University of New Mexico) |
| JAR | Journal of Accounting Research (Wiley-Blackwell) |
| JAR | Joint Aviation Regulation |
| JAR | Juveniles at Risk (various locations) |
| JAR | Journal of Adolescent Research (Sage Publications) |
| JAR | Joint Area Review |
| JAR | Journal of Apicultural Research (International Bee Research Association; UK) |
| JAR | Jesus Adrian Romero (singer) |
| JAR | Jason Andrew Relva (Green Day song) |
| JAR | Jaish Al-Rashideen (Sunni Armed Groups in Iraq) |
| JAR | J August Richards (actor) |
| JAR | Joint Application Requirement |
| JAR | Joint Amended Return (taxes; UK) |
| JAR | Joint Airworthiness Regulations |
| JAR | Japan-A-Radio |
| JAR | Jornadas Argentinas de Robótica |
| JAR | Java Application Resource |
| JAR | Department of Justice Acquisition Regulations |
| JAR | Journalisten Aus Russland (German: Journalists from Russia) |
| JAR | Just Another Rifle |
| JAR | Job Appraisal Review |
| JAR | Joint Acquisition Roadmap |
| JAR | John A. Russell Building (University of Manitoba) |
| JAR | Jack And Retract (jack aircraft and retract landing gear) |