Social Security Retirement

Sirius Satellite Radio

Sonic and the Secret Rings

Soviet Socialist Republic - see Republics of the Soviet Union

Special Service Requirement - supplementary element of PNR

Secondary surveillance radar

Disney's Saratoga Springs Resort & Spa

Self Supporting Run-flat tires, see run flat tires

Security sector reform

Chevrolet SSR, a Chevrolet small truck

Sustained Silent Reading, also called Standardized Sustained Reading

Solid state relay

Solid State Records

The South Saskatchewan Regiment

Slope Stability Radar

Southern Shorthaul Railroad

The sum of squared residuals

Simple Sequence Repeat also called microsatellite.

Southern Suburbs Railway Project in Perth, Western Australia

Structure of Scientific Revolutions, a book by Thomas Kuhn