4M or 4-M may refer to: * 4m, or 4 metres * 4-meter band in amateur radio * 4M, a model of Toyota M engine * 4M, a model of Mitsubishi 4M4 engine * 4M, a model of HP LaserJet 4 * DC-4M, a designation of Canadair North Star * A-4M, a model of Douglas A-4 Skyhawk * Fokker DH-4M, see Airco DH.4 * VF-4M, see VMA-211 * VB-4M, see VMFA-232 * PB-4M, see Osa (handgun) * Sun-4m, a model of Sun-4 workstation * Mayall 4m telescope, see Nicholas U. Mayall Telescope * Meade 4M Community, an astronomy awareness community sponsored by Meade Instruments * LATAM Argentina, a defunct airline based in Buenos Aires, Argentina * J-4M, see Barnett J4B * 4M of manufacture industries are Man, Money, Material and Machine. Also see resource management and Ishikawa diagram. * 4M Software applicatio