Lava

n. molten rock expelled from a volcano; solidified volcanic rock

Lava is molten rock expelled by a volcano during an eruption. When first expelled from a volcanic vent, it is a liquid at temperatures from 700 °C to 1,200 °C (1,300 °F to 2,200 °F). Although lava is quite viscous, with about 100,000 times the viscosity of water, it can flow great distances before cooling and solidifying, because of its thixotropic and shear thinning properties [1], [2].
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Noun
1. rock that in its molten form (as magma) issues from volcanos; lava is what magma is called when it reaches the surface
(hypernym) volcanic rock
(hyponym) aa

n. lava, molten volcanic rock

v. wash, bathe, clean out; swill, lave, launder