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Line breaks: sima
Pronunciation: /ˈsʌɪmə

Definition of sima in English:


[mass noun] Geology , dated
The material of the lower part of the earth’s crust, underlying both the ocean and the continents, characterized as relatively heavy and rich in silica and magnesia. Contrasted with sial.
Example sentences
  • The sial and sima both form the earth's crust which varies in thickness.


early 20th century: blend of silica + magnesium.

Definition of sima in:

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Pronunciation: ɡlɛn
a narrow valley, especially in Scotland or Ireland