| Acronym | Definition |
|---|
| SL | Student Loan |
| SL | Second Life (internet-based virtual world; trademark of Linden Lab) |
| SL | St. Louis (ammunition headstamp) |
| SL | So Long |
| SL | Sri Lanka |
| SL | Straight Line |
| SL | Sign Language |
| SL | Skill Level |
| SL | Stop Loss |
| SL | Sierra Leone |
| SL | Sea Level |
| SL | Sliding |
| SL | Sleeve |
| SL | Standard Level (IB course level) |
| SL | San Luis (Argentina province) |
| SL | Satellite(-borne) Laser |
| SL | Special Linear (mathematics) |
| SL | Single Line |
| SL | Speed Limit |
| SL | Slalom |
| SL | Street Legal |
| SL | Snow Leopard (computer operating system; Apple Computer, Inc.) |
| SL | Squad Leader |
| SL | Sleeper (Indian Railways train class) |
| SL | Source Language (translation) |
| SL | Shelf Life |
| SL | Slime |
| SL | Sick Leave |
| SL | Slough (postcode, United Kingdom) |
| SL | Sublingual (under the tongue) |
| SL | Service Letter |
| SL | Software Library |
| SL | Service Level |
| SL | Sendero Luminoso (Shining Path) |
| SL | Sool (postal region, Somalia) |
| SL | Southern League (AA Baseball Minor League) |
| SL | Senior Level |
| SL | Steam Locomotive |
| SL | San Leandro (California) |
| SL | Storstockholms Lokaltrafik (public transportation in Stockholm, Sweden) |
| SL | Slavic (linguistics) |
| SL | Skylight |
| SL | Simple Life (TV show) |
| SL | Starting Line |
| SL | Sociedad Limitada (Spanish company designation) |
| SL | Stage Left |
| SL | Side Line |
| SL | Scarlet Letter |
| SL | Security Level |
| SL | Service Line |
| SL | Seismic Line |
| SL | System Load |
| SL | Source Level |
| SL | Strong Link (physics) |
| SL | Storage Location |
| SL | Scout Leader |
| SL | Space Lab |
| SL | Superlattice |
| SL | Sea Launch |
| SL | Scan Line |
| SL | Secret Lover |
| SL | Securities Lending (finance) |
| SL | Safety Level |
| SL | Surathkal (station code, Indian Railways |
| SL | Section Leader |
| SL | Structural Level |
| SL | Comet Shoemaker-Levy |
| SL | Standard Label (tapes) |
| SL | Security Layer (telecommunications protocol) |
| SL | Sensitivity Level |
| SL | Safety Limit |
| SL | Sylvan Lake (Alberta, Canada) |
| SL | Saccharum Lactis |
| SL | Sonoluminescence |
| SL | Soap Lake (Washington) |
| SL | Small Leaf (plant physiology) |
| SL | Side Lobe |
| SL | Supervisory Level |
| SL | Shift Leader |
| SL | Switch Locator (US DoD) |
| SL | Shared Lock |
| SL | System Layer |
| SL | Segment Leader |
| SL | Star Lord (Cyberguard firewall) |
| SL | Sand Land (Manga) |
| SL | Shoot Length |
| SL | Soluble Liquid |
| SL | Sisters of Loretto (religious order) |
| SL | Suburban Legends (band) |
| SL | Space Laser |
| SL | Sector Leader (Starkingdoms online game) |
| SL | Sports Light (Mercedes) |
| SL | Sniper Lobby (gaming) |
| SL | Shadow Labs (World of Warcraft gaming) |
| SL | Strictly Linear |
| SL | Signed Log (geocaching) |
| SL | Short Landing |
| SL | Signal Link |
| SL | Specification Limit |
| SL | Stationary Low (power reactor) |
| SL | Shadow Lords (game) |
| SL | Sandia Laboratories |
| SL | Salt Lake City Southern (railroad) |
| SL | Specialised Lending |
| SL | Sensor Link |
| SL | Strouhal Number |
| SL | Sound Locator |
| SL | Summary Links (OSPF) |
| SL | Salvage Loss |
| SL | Shady Limited (clothing brand) |
| SL | Shining Lore (MMORPG) |
| SL | Synchronization Likelihood |
| SL | Solicitor at Law |
| SL | Sport Und Leicht (German, Mercedes-Benz SL) |
| SL | Surface Lease (US and Canada) |
| SL | Stockage Level |
| SL | Strategic List |
| SL | supplier lock |
| SL | Segment Library |
| SL | Symmetric Superlattice |
| SL | Saha-Langmuir (equation) |
| SL | Salem Technical Services |
| SL | Strategic Locator (missing children) |
| SL | Submarine Qualification Lapsed (US Navy) |
| SL | Large Signal Search Light (US Navy) |
| SL | Spontaneous Laughing |