• adt, one of two ISO 639-3 codes for the
Adnyamathanha language, an Australian Aboriginal language •
American death triangle, a deprecated rock climbing anchor system •
Atlantic Daylight Time • Average Daily Theoretical (also known as "theoretical loss" or "theo"), a calculation used to determine gamblers'
casino comps •
Average Daily Traffic, used in transportation planning • Advanced Dvorak Technique - a technique developed on the basis of the
Dvorak technique to estimate the intensity of tropical cyclones