Dir, dir, or DIR may refer to:

• De Imperatoribus Romanis, an online biographical encyclopedia of the Roman emperors from 27 BC to 1453 AD
• Detroit International Riverfront, an area of Detroit, Michigan in the United States
• Developmental, Individual differences, Relationship-based approach, a developmental intervention to autism
• Digitally Imported Radio, an internet radio station
• Digital Instrumentation Recorder, a magnetic tape format by Sony
• Doing It Right, a methodology for scuba diving
• Double inversion recovery, an MRI sequence

• An abbreviation for directory (file systems)
• dir (command), a shell command
• directory (OpenVMS command), an operating system command
• <dir>...</dir>, an HTML element

• Dir, Pakistan, a town in the Khyber Pakhtunkhwa province of Pakistan
• Dir (union council), an administrative unit in the Khyber Pakhtunkhwa province of Pakistan
• Dir (princely state), a former princely state in the North-West Frontier Province, incorporated into Pakistan in 1969
• Dir District in the North West Frontier Province, split into two districts in 1996

• Australian Government Department of Industrial Relations (1978–1982)
• Australian Government Department of Industrial Relations (1987–1997)
• California Department of Industrial Relations
• Texas Department of Information Resources

• Dir (clan), one of the five major Somali clans
• Askold and Dir, Viking rulers of Kiev

• Dirr (disambiguation)
• Durr (disambiguation)
• Duerr (disambiguation)