si·​al | \ ˈsīˌal \
plural -s

Definition of sial

 (Entry 1 of 2)

1 : siliceous or acid igneous rock whether solid or molten
2 : the lighter outer portion of the earth composed mainly of solid or molten rocks rich in silica and alumina — compare sima
variants: or sialo-

Definition of sial- (Entry 2 of 2)

: saliva sialolith

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History and Etymology for sial


German, from New Latin silicium + aluminium

Combining form

New Latin, from Greek, from sialon; akin to Latin spuere to spit

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Cite this Entry

“Sial.” The Dictionary, Merriam-Webster Inc., Accessed 22 January 2020.

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