Basalt is a type of black rock that is produced by volcanoes.
basalt in British English
(ˈbæsɔːlt)
noun
1.
a fine-grained dark basic igneous rock consisting of plagioclase feldspar, a pyroxene, and olivine: the most common volcanic rock and usually extrusive
flood basalt
2.
a form of black unglazed pottery resembling basalt
Derived forms
basaltic (baˈsaltic)
adjective
Word origin
C18: from Late Latin basaltēs, variant of basanītēs, from Greek basanitēs touchstone, from basanos, of Egyptian origin
basalt in American English
(bəˈsɔlt; ˈbeɪˌsɔlt; ˈbæsˌɔlt)
noun
1.
a dark, fine-grained, usually extrusive igneous rock that is more basic than andesite, consisting chiefly of plagioclase feldspars and pyroxene: often found in vast sheets, it is the most common extrusive igneous rock
2.
a kind of unglazed, black pottery designed by Josiah Wedgwood
: also baˈsaltˌware
Derived forms
basaltic (baˈsaltic) (bəˈsɔltɪk)
adjective
Word origin
earlier basaltes < L, a dark Ethiopian marble: term used by Pliny for basanites < Gr basanitēs, species of slate used to test gold < basanos, touchstone, test (ult. < Egypt bḫnw) + -itēs, -ite1