Definition of atom. 1  1a : the smallest particle of an element that can exist either alone or in combination an atom of hydrogenb : the atom considered as a source of vast potential constructive or destructive energy â¦ a largely forgotten legacy of this country's conquest of the atom.
The mountain, a part of the Cascade Range, is a volcano that has not erupted for 2,000 years. It is also the highest mountain in the state of Washington. English explorer George Vancouver named Mount Rainier in honor of another navigator, Peter Rainier. Some people, however, prefer to call the mountain by its Indian name, Mount Tacoma.
On March 2, 1899, President William McKinley signed a bill passed by Congress authorizing the creation of Mount Rainier National Park, the nation's fifth national park. It was the first national park created from a national forest. The Pacific Forest Reserve had been created in 1893 and included Mount Rainier.