sial

1 of 2

noun

si·​al

ˈsīˌal

plural -s

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

sial-

2 of 2

combining form

variants or sialo-

: saliva

sialolith

Word History

Etymology

Noun

German, from New Latin silicium + aluminium

Combining form

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

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