ATD

ATD may refer to:

• Association for Talent Development, formerly American Society for Training and Development
• the postal code of Attard, Malta
• Against the Day, a Thomas Pynchon novel
• Attention To Detail, a British game development studio that liquidated in late 2003

Computing and technology

• Anthropomorphic test device, also known as a crash test dummy
• at (Unix) or @daemon (spelled "atd", lower case), a standard Unix program that runs user-specified daemon handling commands at scheduled deferred times
• Azimuth tractor drive, a drive system for tugboats

Medicine and science

• 1,4,6-Androstatrien-3,17-dione, estrogen inhibitor
• Anti Thyroid drugs
• Acute Tryptophan Depletion