crack, scissure, cleft, crevice, fissure - a long narrow opening

eructation, extravasation, eruption - (of volcanos) pouring out fumes or lava (or a deposit so formed)

active - (of e.g. volcanos) erupting or liable to erupt; "active volcanos"

Asama, Mount Asama - a volcano in central Honshu near Nagano; one of the largest volcanoes in Japan (8,340 feet)

Mount Pinatubo, Pinatubo - a volcano on Luzon northwest of Manila; erupted in 1991 after 600 years of dormancy

Cameroon - an inactive volcano in western Cameroon; highest peak on the West African coast

Citlaltepetl, Mount Orizaba, Mt Orizaba, Pico de Orizaba - an extinct volcano in southern Mexico between Mexico City and Veracruz; the highest peak in Mexico (18,695 feet)

Colima, Nevado de Colima, Volcan de Colima - an active volcano in southwestern Mexico

Cotacachi - an Andean volcano in northern Ecuador; last erupted in 1955

Cotopaxi - the world's largest active volcano; located in the Andes in north central Ecuador

Demavend - an active volcano in northern Iran

El Misti - the world's 2nd largest active volcano; located in the Andes in southern Peru

Etna, Mount Etna, Mt Etna - an inactive volcano in Sicily; last erupted in 1961; the highest volcano in Europe (10,500 feet)

Fuego - a volcano in south central Guatemala

Fuji-san, Fujinoyama, Fujiyama, Mount Fuji, Fuji - an extinct volcano in south central Honshu that is the highest peak in Japan; last erupted in 1707; famous for its symmetrical snow-capped peak; a sacred mountain and site for pilgrimages

Galeras, Pasto - an active volcano in southeastern Colombia in the Andes

Guallatiri - the world's highest volcano; in the Andes in northern Chile; last erupted in 1959

Huainaputina - an inactive volcano in the Andes in southern Peru; last erupted in 1783

Klyuchevskaya - an inactive volcano on the Kamchatka Peninsula; last erupted in 1946

Krakatao, Krakatau, Krakatoa - a small volcanic island in Indonesia between Java and Sumatra; its violent eruption in 1883 was the greatest in recorded history

Lascar - a volcano in the Andes in Chile

Mauna Kea - an active volcano on north central Hawaii Island; highest peak in the Hawaiian Islands

Mauna Loa - an active volcano on south central Hawaii Island

Nyamuragira - an active volcano in eastern Congo

Nyiragongo - an active volcano in eastern Congo

Purace - an inactive volcano in the Andes in southern Colombia; last erupted in 1950

Sangay - an inactive volcano in the Andes in central Ecuador; last erupted in 1946

Tupungatito - an inactive volcano in central Chile; last erupted in 1959

Mount Saint Helens, Mount St. Helens, Mt. St. Helens - an active volcano in the Cascade Range in southwestern Washington; erupted violently in 1980 after 123 years of inactivity

Mount Vesuvius, Mt. Vesuvius, Vesuvius - a volcano in southwestern Italy on the Mediterranean coast; a Plinian eruption in 79 AD buried Pompeii and killed Pliny the Elder; last erupted in 1944

mountain, mount - a land mass that projects well above its surroundings; higher than a hill

crater, volcanic crater - a bowl-shaped opening at the top of a volcano