STL is a TLA that can stand for

• Licentiate of Sacred Theology
• Sea Train Lines, Inc.
• Simulation and Test Language
• Slime Time Live (Nickelodeon)
• Slouching Toward Liverpool
• Slower than light - the opposite of faster-than-light
• Société de transport de Laval (Public transit in Laval, QC Canada)
• Software Technologies Laboratory (Private company in Blacksburg, Virginia; originally part of Virginia Tech)
• Software Tool Library
• Solaris Threading Library (Sun Microsystems API)
• Space Technology Laboratories (a former division/subsidiary of the Ramo-Wooldridge Corporation, later TRW, Inc. — taken over by Northrop Grumman at the end of 2002)
• St. Louis, Missouri, USA - IATA airport code for Lambert-Saint Louis International Airport
• Standard Telecommunications Laboratories (the R&D arm of Standard Telephone and Cable)
• Standard telegraph level
• Standard Template Library (for C++)
• State logic, a PLC programming language.
• Statement list, a Siemens Simatic version of a PLC instruction list programming language.
• Steel
• Stereolithography
• STL (file format), a file format for stereolithography and other solid freeform fabrication technologies
• Stockage List
• Store Team Leader (Target stores employee title)
• Strike Team Leader
• Structured Translator Language (IBM)
• Studio/transmitter link
• System Threat Library

• Réseau de transport de Longueuil, sometimes erroneously called the Societe de transport de Longueuil, or STL.

STL | STL | STL | STL