| Acronym | Definition |
|---|
| SQ | Square |
| SQ | Singapore Airlines |
| SQ | Sound Quality |
| SQ | Service Quality (TL 9000) |
| SQ | Squadron |
| SQ | Squeezed (Files) |
| SQ | Stock Quote |
| SQ | Space Quest |
| SQ | Subcutaneous |
| SQ | Squall (METAR weather) |
| SQ | Sureté du Québec (Provincial Police) |
| SQ | Super Quiet |
| SQ | Sigma Quality (Six Sigma quality benchmark) |
| SQ | Seismically Qualified |
| SQ | South Qeynos (gaming, Everquest) |
| SQ | Social Quotient (Van Sloan) |
| SQ | Stupid Question |
| SQ | Signal Quality |
| SQ | Significant Quantity (nuclear weapons, fission: IAEA term for the amount of fissile material necessary) |
| SQ | Special Quotation (Japanese stock market) |
| SQ | Systemizing Quotient |
| SQ | Scalar Quantization |
| SQ | San Quentin Prison (San Quentin, CA) |
| SQ | Soldier Qualification (Canadian Forces) |
| SQ | Stereo Quadraphonic (Columbia Records quadraphonic system) |
| SQ | Student Questionnaire |
| SQ | Side-Quest (gaming) |
| SQ | Superquick |
| SQ | Stephan's Quintet |
| SQ | Système Qualité (French: Quality System) |
| SQ | Shortest Queue |
| SQ | Subject to Quotation |
| SQ | Slack Quenching |
| SQ | Sound Que (theater terminology) |
| SQ | Safety Quotient |
| SQ | Squad member but no letter (National Collegiate Athletic Association) |