or tach·y·lite

[ tak-uh-lahyt ]
/ ˈtæk əˌlaɪt /

noun Petrography.

a black, glassy form of basalt, readily fusible and of a high luster.

Origin of tachylyte

First recorded in 1865–70; tachy- + -lyte2

Related forms

tach·y·lit·ic [tak-uh-lit-ik] /ˌtæk əˈlɪt ɪk/, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for tachylyte



/ (ˈtækɪˌlaɪt) /


a black basaltic glass often found on the edges of intrusions of basalt

Derived Forms

tachylytic (ˌtækɪˈlɪtɪk) or tachylitic, adjective

Word Origin for tachylyte

C19: from German Tachylit, from tachy- + Greek lutos soluble, melting, from luein to release; so called because it fuses easily when heated. The form tachylite is influenced by -lite stone
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012