(aviation) Initialism of total time since new: the duration of time for which an aircraft has been in active use since its manufacture.

(sports) Abbreviation of Toronto.

(biochemistry) Abbreviation of transthyretin. / (linguistics) Abbreviation of type-token ratio.

(Internet slang) Abbreviation of to the rescue.

(aviation and travel) Initialism of ticket time limit. / (computing, networking) Initialism of time to live. / (electronics) Initialism of transistor–transistor logic.

(Internet slang) Initialism of to tell the truth.

Initialism of total trihalomethanes.

plural of TTIP

(chemistry) Initialism of titanium isopropoxide. (a chemical compound)

(trade) Initialism of Transatlantic Trade and Investment Partnership. (a proposed free trade area between the United States and the European Union)