Word
basalt
US/bəˈsɔɫt/
UK/bˈæsɒlt/
Definitions
01volcanic rock
n. a dark, hard rock that forms when lava from a volcano cools down quickly.
n. a fine-grained, dark mafic igneous rock, typically volcanic in origin, that constitutes the majority of the Earth's oceanic crust.
“The island's beaches are famous for their black sand made from crushed basalt.”
“Geologists identified the formation as columnar basalt, created by the contraction of thick lava flows as they cooled over several centuries.”
Technical
Usage
Uncountable when referring to the material; countable when referring to specific types or formations.
Teaching tip
This is a specific geological term; students should distinguish it from general 'lava' or 'granite'.
Synonyms
02pottery
n. a type of hard, black pottery that does not have a shiny coating.
n. a variety of black, unglazed stoneware, originally developed by Josiah Wedgwood to resemble the volcanic rock.
“The museum displayed a beautiful 18th-century vase made of black basalt.”
“The artisan specialised in basalt ware, utilizing the matte finish of the unglazed stoneware to highlight the intricate classical engravings.”
Technical · Formal
Usage
Often used as a modifier, as in 'basalt ware'.
Teaching tip
This sense is rare outside of art history or antique collecting contexts.
Synonyms
Real-World Examples
“Basalt, andesite, and granite can contain as much as 75 percent silicon dioxide.” “Spreading finely crushed basalt across farmland has been promoted as a relatively simple way to remove large quantities of carbon dioxide from the atmosphere.” Etymology
From Late Latin basaltes, a misspelling of Latin basanites, from Ancient Greek βασανίτης (basanítēs), from βάσανος (básanos, “touchstone”), from Egyptian bḫn (“a hard stone”), b-x:n-O39
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.