| Acronym | Definition |
|---|
| RAS | Remote Access Service(s) |
| RAS | IEEE Robotics and Automation Society |
| RAS | Radar Absorbent Structure |
| RAS | Radar Altimeter Set |
| RAS | Radar Augmentation System |
| RAS | Radial Arm Saw |
| RAS | Radio Astronomy Service |
| RAS | Rail Accessory System |
| RAS | Random Access Storage |
| RAS | Rat Sarcoma |
| RAS | Rates And Services (Pacific Gas & Electric Company) |
| RAS | Reactor Analysis and Safety |
| RAS | Readiness Assessment System (GCCS) |
| RAS | Rear Area Security |
| RAS | Rebellion Against School |
| RAS | Receiver Adjacent Signal |
| RAS | Record Association System |
| RAS | Recovery Activation Signal |
| RAS | Recursive Acronym Syndrome |
| RAS | Redundant Acronym Syndrome |
| RAS | Reference Assembly Sequence |
| RAS | Refractive Aberrated Simulator |
| RAS | Regimental Aid Station |
| RAS | Regimental Aviation Squadron |
| RAS | Regione Autonoma di Sardegna (Italy) |
| RAS | Registration Authority Support |
| RAS | Registration, Admission, and Status (ITU-T Recommendation H.323) |
| RAS | Reliability, Availability & Serviceability |
| RAS | Remedial Action Selection (process/report) |
| RAS | Remote Access Server |
| RAS | Remote Access Software |
| RAS | Remote Access Switch |
| RAS | Remote Access System |
| RAS | Remote Active Spectrometer |
| RAS | Remote Airborne Sensor (RFINT sensor carried on board the U-2 aircraft) |
| RAS | Remote Alarm Station |
| RAS | Remote Analog Scanner |
| RAS | Remote Antenna Site |
| RAS | Renal Artery Stenosis |
| RAS | Renal-Angiotensin System (cardiology) |
| RAS | RePEc (Research Papers in Economics) Author Servive |
| RAS | Replenishment At Sea |
| RAS | Replication At Sending |
| RAS | Report Application Server (Crystal Reports) |
| RAS | Request Automation System |
| RAS | Required At Site |
| RAS | Research Associates of Syracuse, Inc. |
| RAS | Research, Analysis & Statistics (US IRS) |
| RAS | Reserve Advisor Squadron |
| RAS | Reserve Airlift Support |
| RAS | Resource Access System |
| RAS | Resource Allocation Software |
| RAS | Restroom Association of Singapore |
| RAS | Reticular Activating System (Neurologic Physiology) |
| RAS | Retiree Account Statement (US DoD DFAS) |
| RAS | Return Address Stack |
| RAS | Return Air Sensor |
| RAS | Returned Activated Sludge |
| RAS | Reusable Absorbent System |
| RAS | Reusable Asset Specification |
| RAS | Revenue Accounting System |
| RAS | Rien A Signaler (French: Nothing Noticeable) |
| RAS | Right Analog Stick (game controllers) |
| RAS | Riunione Adriatica di Sicurtà (Adriatic insurances company, Italy) |
| RAS | River Analysis System |
| RAS | River Assault Squadron |
| RAS | Riverside Adult School (California) |
| RAS | Robert Alexander Schumann (classical composer) |
| RAS | Roll Angle Sensor (spacecraft instrument) |
| RAS | Roll Aspect System |
| RAS | Romanian Airport Services |
| RAS | Routine Analytical Services |
| RAS | Row Access Strobe (less common) |
| RAS | Row Address Select |
| RAS | Row Address Signal (computer memory) |
| RAS | Row Address Strobe |
| RAS | Royal African Society |
| RAS | Royal American Shows LLC (Tampa, FL) |
| RAS | Royal Asiatic Society |
| RAS | Royal Astronomical Society (British) |
| RAS | Run and Shoot (game) |
| RAS | Rundfunk-Anstalt Südtirol |
| RAS | Running and Screaming |
| RAS | Running Around Screaming |
| RAS | Russian Academy of Science |
| RAS | Sun Raster Format (filename extension) |
| RAS | Raster Image |
| RAS | Rear Access System |
| RAS | Reassign Allowance Sectors |
| RAS | Registration Admission and Status |
| RAS | Registration Authorities |
| RAS | Reliability Availability and Serviceability |
| RAS | Remote Administrator Server |
| RAS | Remote Authentication Service |
| RAS | Resource Allocation System |