pillow lava
noun Geology.
lava in the form of an agglomeration of rounded, pillow-shaped masses, the result of subaqueous or subglacial volcanic eruption.
Origin of pillow lava
First recorded in 1900–05
Words nearby pillow lava
pillory,
pillow,
pillow block,
pillow fight,
pillow lace,
pillow lava,
pillow sham,
pillow splint,
pillow sword,
pillow talk,
pillowcase
British Dictionary definitions for pillow lava
pillow lava
noun
lava that has solidified under water, having a characteristic structure comprising a series of close-fitting pillow-shaped masses
Scientific definitions for pillow lava
pillow lava
[ pĭl′ō ]
Lava that forms from an underwater eruption and is characterized by pillow-shaped masses. Pillow lava forms when hot lava is suddenly exposed to cold water, forming a sacklike membrane that is filled with additional cooling and solidifying lava. The outer membrane is usually finer grained than the inner lava.