Tactical Hit Indicator (SAUS)
Tai Long - Language code (ETLW)
Telehop, Inc. - Fresno, CA - Telecommunications (TSSD)
Temperature-Humidity Index
Terre Haute - Indiana - Seismograph station code, US Geological Survey (SEIS)
Texas Heart Institute - University of Texas - Research center (RCD)
Theodor Herzl Institute (EA)
Thermo Instrument Sys - AMEX symbol
Thermo Instrument Systems, Inc. - AMEX symbol (SPSG)
Thing (automobile) - NCIC car model code
Thios Resources (SAUS)
Thios Resources, Inc. - Vancouver Stock Exchange symbol
Third Harmonic Index (SAUS)
Time Handed In - Navy
Total Height Index (OA)
Trans Healthcare, Inc. (MHID)
Transient Hypogammaglobinemia of Infancy - Immunology (DAVI)
Travelers Health Institute - Later, ITHI
Trihydroxyindol - Organic chemistry
Trihydroxyindole (STED)
Trinity Health International