MID explained

MID or Mid may refer to:

Computers and electronics

MapInfo Interchange Format; .mid is also sometimes used as the filename extension for some MapInfo files
Media Identification Code (MID code), a code indicating the manufacturer of a DVD
Mobile Internet device, a category of mobile computer
Molded interconnect device, an injection molded thermoplastic part with integrated electronic circuit traces
Multiple interface declaration, a construct in some computer programming languages
Musical Instrument Digital Interface, .mid is sometimes used as an alternate filename extension for MIDI files

Multi-infarct dementia, a disease also known as vascular dementia
Minimal important difference, the smallest improvement felt to be meaningful by a patient
Monocyte, a type of white blood cell in the innate immune system of vertebrates

Maritime identification digits, a 3-digit code identifying the country of a ship/coastal station using communication equipment.
Mentioned in dispatches, a military award for gallantry or otherwise commendable service
Militarized interstate dispute, conflicts between states that do not involve full-scale wars
Military Intelligence Division (United States), a former military intelligence branch of the United States Army

Integration and Development Movement, a political party in Argentina
Ministry of Foreign Affairs (Russia), for which MID is a colloquial term
Monastic Interreligious Dialogue, the American arm of the DIMMID, an interfaith movement

Mérida International Airport (IATA: MID)
Middletown station (Pennsylvania) (Amtrak station code: MID)
Modesto Irrigation District, a special district in California
Mortgage interest deduction, a tax deduction for mortgage interest paid by homeowners
Measuring Instruments Directive
Mid vowel
Midfielder, a position in association football