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VOLCANIC ROCK
| Pronunciation (US): |  | (GB): | |
I. (noun)
Sense 1
Meaning:
Extrusive igneous rock solidified near or on the surface of the Earth
Classified under:
Hypernyms ("volcanic rock" is a kind of...):
igneous rock (rock formed by the solidification of molten magma)
Hyponyms (each of the following is a kind of "volcanic rock"):
agglomerate (volcanic rock consisting of large fragments fused together)
amygdaloid (volcanic rock in which rounded cavities formed by expanding gas have subsequently become filled with mineral deposits)
dacite (a grey volcanic rock containing plagioclase and quartz and other crystalline minerals)
basalt (the commonest type of solidified lava; a dense dark grey fine-grained igneous rock that is composed chiefly of plagioclase feldspar and pyroxene)
volcanic glass (a kind of natural glass produced when molten lava cools very rapidly)
lava (rock that in its molten form (as magma) issues from volcanos; lava is what magma is called when it reaches the surface)
tufa; tuff (hard volcanic rock composed of compacted volcanic ash)
