Also found in: Dictionary, Thesaurus, Medical, Legal, Acronyms, Idioms, Wikipedia.
MID(1) The file extension for Musical Instrument Digital Interface files (see MIDI file).
(2) (Mobile Internet Device) Intel's moniker for a low-cost handheld computer that has wireless capability. The term was coined when Intel introduced its Atom chips in 2008. MIDs are larger than smartphones and smaller than netbooks. See Intel Atom.