Word Study
trachyte
CIDE DICTIONARY
trachyte, n. [Gr. rough, rugged: cg. F. trachyte.].
An igneous rock, usually light gray in color and breaking with a rough surface. It consists chiefly of orthoclase feldspar with sometimes hornblende and mica. [1913 Webster]
OXFORD DICTIONARY
trachyte, n. a light-coloured volcanic rock rough to the touch.
Derivative
trachytic adj.
Etymology
F f. Gk trakhutes roughness (as TRACHOMA)
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