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.
Although Rainier had been considered the official name of the mountain, Theodore Winthrop, in his posthumously published 1862 travel book The Canoe and the Saddle, referred to the mountain as Tacoma and for a time, both names were used interchangeably, although Mt. Tacoma was preferred in the city of Tacoma.ount Rainier is one of the 16 Decade Volcanoes. The most recent recorded volcanic eruption was between 1820 and 1854, but many eyewitnesses reported eruptive activity in 1858, 1870, 1879, 1882 and 1894 as well. Although Mount Rainier is an active volcano, as of 2010 there was no evidence of an imminent eruption.