TSI

TSI may refer to:

*TeleSensory, Inc., a maker of speech products and products intended for the blind
*Televisione svizzera di lingua italiana Swiss television in the Italian language.
*"The Spaghetti Incident?", a covers album by Guns N' Roses.
*Thyroid Stimulating Immunoglobulin
*Torres Strait Islanders, an Australian indigenous people
*Torres Strait Islands
*Time-Slot Interchange, a technique used to switch networks
*Trading Standards Institute, a British professional association
*Town Sports International, an operator of fitness facilities
*Total Solar Irradiance - The total energy output of the sun
*Trophic state index
*TSI Inc, an instrument company headquartered in St. Paul, MN
*TSI, Turbocharged Stratified Injection or Twincharged Stratified Injection, a technology available on some engines offered by Volkswagen Group.
*TSI, Triple Sugar Iron test, TSI slant - A microbiological test for enteric bacteria such as Salmonella and Shigella.
*TSI, Technical Specification for Interoperability for the European railway system