| SAARC |
South Asian Association for Regional Cooperation |
| SAC |
Space Application Centre |
| SAFTA |
 South Asian Free Trade Agreement |
| SAI |
Sports Authority of India |
| SAIL |
Steel Authority of India Limited |
| SAPTA |
South Asian Preferential Trade Arrangement |
| SARS |
Severe Acute Respiratory Syndrome |
| SC |
Security Council/Supreme Court |
| SCI |
Shipping Corporation of India |
| SCOPE |
Standing Conference of Public Enterprises |
| SCRA |
Special Class Railway Apprentice |
| SCSI |
Small Computer Systems Interface |
| SDR |
Special Drawing Rights |
| SEBI |
Securities and Exchange Board of India |
| SENSEX |
Sensitivity Index (of Share Price) |
| SEZ |
Special Economic Zone |
| SGPC |
Siromani Gurudwara Prabandak Committee |
| SHAR |
Shri Harikota Range |
| SIM |
Subscriber Information Module |
| SIS |
Secret Intelligence Service (U.K) |
| SITA |
Suppression of Immoral Traffic in Women and Girls Act |
| SlDBI |
Small Industries Development Bank of India |
| SLV |
Satellite Launch Vehicle |
| SMS |
Short Message Service |
| SMTP |
Simple Mail Transfer Protocol |
| SPCA |
Society for the Prevention of Cruelty of Animals |
| SPIC MACAY |
Society for the Promotion of Indian Classical music and culture |
| SRS |
 Sample Registration System |
| STARS |
Satellite Tracking and Ranging Station |
| STD |
Subscriber Trunk Dialling; Sexually Transmitted Diseases |
| STPI |
Software Technology Parks of India |
| SWAPO |
South West African People's Organisation |
| TA |
Traveling Allowance/Territorial Army |
| TADA |
Terrorist and Disruptive Activities (Prevention) Act |
| TC |
Transfer Certificate, Trusteeship Council |
| TCP |
Transfer Call Protocol<br> Transmission Control Protocol |
| TELCO |
Tata Engineering and Locomotive Company |
| TELEX |
Tele-printer Exchange |
| TERCOM |
Terrain Contour Matching |
| TFT |
Thin-Film Transistor |
| TIFR |
Tata Institute of Fundamental Research |
| TISCO |
Tata Iron and Steel Company |
| TNT |
Tri-nitro-toluene |
| TOEFL |
Test of English as a Foreign Language |
| TRAI |
Telecom Regulatory Authority of India |
| TRIPS |
Trade Related Intellectual Property Rights |
| TTE |
Traveling Ticket Examiner |
| TTFI |
Table Tennis Federation of India |
| TWA |
Trans World Airlines (USA) |
