- (metrology) Symbol for the terawatt, an SI unit of power equal to 1012 watts.
- The ISO 3166-1 two-letter (alpha-2) code for Taiwan.
TW (plural TWs)
- (gemstones) Initialism of total weight. (in carats).
- (pharmacology) Initialism of treatment week.
- (LGBT) Initialism of trans woman.
- Initialism of trigger warning.
Perhaps from the Telex input method whereby either that the W key can be pressed to type in the letter ư or to add the diacritical side horn to an already typed u to form the ư, and intended to be this way to distinguish from tư as an actual word.
- Abbreviation of trung ương.