1. plural of volcano; mountains or hills with openings through which lava, rock fragments, hot vapor, and gas are or have been erupted from the earth’s crust

Examples

• The Hawaiian islands were formed by underwater volcanoes.
• Active volcanoes can be extremely dangerous to nearby communities.
• Scientists study volcanoes to predict when they might erupt.
• The Ring of Fire contains many of the world’s most active volcanoes.
• Extinct volcanoes no longer pose a threat of eruption.
• Mount Vesuvius is one of the most famous volcanoes in history.