sial

American

[sahy-al] / ˈsaɪ æl /

noun

Geology.

the assemblage of rocks, rich in silica and alumina, that comprise the continental portions of the upper layer of the earth's crust.

sial British

/ ˈsaɪəl, saɪˈælɪk /

noun

the silicon-rich and aluminium-rich rocks of the earth's continental upper crust, the most abundant individual rock being granite

"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

Other Word Forms

sialic adjective

Etymology

Origin of sial

1920–25; < German, equivalent to Si ( licium ) silicium + Al ( uminium ) aluminum

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

VII-X, by Arnold Toynbee, brought to an end the most massive and controver sial historical inquiry since Spengler.

From Time Magazine Archive

He loved controver- sial reporting, and this had the makings of .

From Terminal Compromise: computer terrorism: when privacy and freedom are the victims: a novel by Schwartau, Winn

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023