What does TTZ stand for?

Tactical-Technical Assignment - Army

Tilcon Tomasso - Federal Railroad Administration identification code

Titizima - Bonin Islands - Seismograph station code, US Geological Survey - Closed (SEIS)

Tornquist-Teisseyre Zone - Geology

Transformation Toughened Zirconia - Metallurgy

Treats, Inc. - Toronto Stock Exchange symbol

Tsum - Language code (ETLW)