M19, M.19, or M-19 most commonly refers to: May 19th Communist Organization (M19), an American far-left female-led group active during the 1970s–1980s 19th of April Movement (M-19), a former Colombian guerrilla movement and political party 1970–1990
M19, M.19, or M-19 may also refer to:
In science Messier 19 (M19), a globular cluster in the constellation Ophiuchus
In transportation M-19 (Michigan highway), a state highway in Michigan, U.S. M19 (East London), a Metropolitan Route in East London, South Africa M19 (Cape Town), a Metropolitan Route in Cape Town, South Africa M19 (Johannesburg), a Metropolitan Route in Johannesburg, South Africa M19 (Pretoria), a Metropolitan Route in Pretoria, South Africa M19 (Durban), a Metropolitan Route in Durban, South Africa M19 (Bloemfontein), a Metropolitan Route in Bloemfontein, South Africa M19 (Port Elizabeth), a Metropolitan Route in Port Elizabeth, South Africa M19 expressway (Hungary) M19 road (Zambia), a short road in Zambia
In firearms and military equipment M19 mine, a United States anti-tank mine Smith & Wesson Model 19 (S&W M19), a Smith & Wesson revolver Mk 19 grenade launcher, a belt-fed automatic grenade launcher M.19, an internal Fokker designation for the Fokker D.III, a 1916 German single-seat fighter aircraft M19 mortar M19 tank transporter M19 gun motor carriage M19 Maschinengranatwerfer – a German mortar used during WW2