Donald Baxter MacMillan (November 10, 1874 – September 7, 1970) was an American explorer, sailor, researcher and lecturer who made over 30 expeditions to the Arctic during his 46-year career. He pioneered the use of radios, airplanes, and electricity in the Arctic, brought back films and thousands of photographs of Arctic scenes, and put together a dictionary of the Inuktitut language.