| Acronym | Meaning |
 | SSA | 1/0 GCOS Program Element Name |
 | SSAT | Shuttle Service And Access Tower |
 | SSAT | SPace Shuttle Access Tower (now FSS) |
 | SSB | Single Sideband |
 | SSB | Source Selection Board |
 | SSBC | Summary Sheet Bar Chart |
 | SSC | Shuttle System Contractor |
 | SSC | Single-Stage Command |
 | SSC | Solid-Solution Cermet |
 | SSC | Subsystem Computer |
 | SSC | Subsystem Sequence Controller |
 | SSC | L Shuttle System Commonality List |
 | SSCA | Surface Sampler Control Assembly |
 | SSCC | Support Services Control Center |
 | SSCHS | Space Shuttle Cargo Handling System |
 | SSCP | Small Self-Contained Payloads |
 | SSCSP | Space Shuttle Crew Safety Panel |
 | SSD | Spacecraft Software Division |
 | SSD | System Summary Display |
 | SSDD | Software System Design Document |
 | SSDH | Subsystem Data Handbook |
 | SSDS | Space Station Data System |
 | SSE | Space Shuttle Engines |
 | SSE | Subsystem Element |
 | SSE | SubsYstem Support Equipment |
 | SSEOS | Space Shuttle Engineering And Operations Support |
 | SSF | SRB Storage Facility |
 | SSFGSS | Space Shuttle Flight And Ground System Specification |
 | SSFL | Santa Susana Field Laboratory |
 | SSFS | Space Shuttle Functional Simulator |
 | SSHB | Station Set Handbook |
 | SSI | Significant Structural Item |
 | SSIBD | Shuttle System Interface Block Diagram |
 | SSID | Shuttle Stowage Installation Drawing |
 | SSIP | Systems Software Interface Processing |
 | SSIS | Space Station Information System |
 | SSITP | Shuttle System Integrated Test Plan |
 | SSL | System Software Loader |
 | SSM | SPacecraft Systems Monitor |
 | SSM | Subsystem Manager |
 | SSM | Support System Module |
 | SSM | Systems Support Module |
 | SSM | BSpace Shuttle Maintenance Baseline |
 | SSM | ESpace Shuttle Main Engine |
 | SSM | EC Space Shuttle Main Engine Controller |
 | SSME | Space Shuttle Main Engine |
 | SSMECA | Space Shuttle Main Engine Controller Assembly |
 | SSMECA | SSM E Controller Assembly |
 | SSO | Safety Signification Operation |
 | SSO | Source Selection Official |