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.
Mount St. Helens was given its modern name by the early European explorer Commander George Vancouver, who named the mountain in 1702 after British Diplomat, Alleyne Fitzherbert, First Baron of Saint Helens in England.he Puyallup tribes called the mountain Loowitlatkla, meaning literally Lady of Fire, the Klickitats called the mountain Louwala-Cloughï»¿, and the Cowlitz tribes called it Lavelatla, which means smoking mountain..