volcanovolcano /vɑlˈkeɪnoʊ/ ●●○ noun (plural volcanoes or volcanos) [countable] 
earth science, geography a mountain with an opening at the top through which hot rocks and ash sometimes rise into the airCOLLOCATIONSverbsa volcano erupts (=it sends out ash, hot rock, etc.) The last time the volcano erupted was 50 years ago.a volcano spews lava/ash/steam/rocks (=it sends them out into the air) The volcano continues to spew ash across the island.adjectivesan active volcano (=it may erupt at any time) Mount Etna is an active volcano.a dormant volcano (=it has not erupted for a long time but may erupt some time) Volcanoes can remain dormant for hundreds of years.an extinct volcano (=it does not erupt any more) The town is near an extinct volcano.
earth science, geography a mountain with an opening at the top through which hot rocks and ash sometimes rise into the airCOLLOCATIONSverbsa volcano erupts (=it sends out ash, hot rock, etc.) The last time the volcano erupted was 50 years ago.a volcano spews lava/ash/steam/rocks (=it sends them out into the air) The volcano continues to spew ash across the island.adjectivesan active volcano (=it may erupt at any time) Mount Etna is an active volcano.a dormant volcano (=it has not erupted for a long time but may erupt some time) Volcanoes can remain dormant for hundreds of years.an extinct volcano (=it does not erupt any more) The town is near an extinct volcano.