syenite

American  

[sahy-uh-nahyt] / ˈsaɪ əˌnaɪt /

noun

1. a granular igneous rock consisting chiefly of orthoclase and oligoclase with hornblende, biotite, or augite.

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syenite British  

/ ˌsaɪəˈnɪtɪk, ˈsaɪəˌnaɪt /

noun

1. a light-coloured coarse-grained plutonic igneous rock consisting of feldspars with hornblende or biotite

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syenite Scientific  

/ sī′ə-nīt′ /

1. A light-colored, coarse-grained igneous rock consisting primarily of alkali feldspar together with some mafic minerals, especially hornblende. Unlike most igneous rocks, syenite has little or no quartz. It is believed to form from the cooling of magma that forms at very high temperatures and at great depths. It is the coarse-grained equivalent of trachyte.

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Other Word Forms

• syenitic
  adjective

Etymology

Origin of syenite

First recorded in 1790–1800; from Latin syēnītēs (lapis) “(stone) of Syene” (the ancient name of Aswan, an Egyptian city on the Nile), from Greek syēnī́tēs (líthos); see -ite ¹

Example Sentences

See Examples For:

syenite

Rocks labeled as ‘granite’ in laymen applications can be several other rocks, including syenite, tonalite, and monzonite.

From Textbooks ● Jan. 1, 2017

Most of these tracks end behind large boulders of dolostone or syenite, some however start and end without an apparent object nearby.

From Scientific American ● Jul. 22, 2013

The molten trap broke through at various times, and presenting various appearances, but in nearly the same centre; here existing as an augitic rock, there as a syenite, yonder as a basalt or amygdaloid.

From The Cruise of the Betsey or, A Summer Ramble Among the Fossiliferous Deposits of the Hebrides. With Rambles of a Geologist or, Ten Thousand Miles Over the Fossiliferous Deposits of Scotland by Symonds, W. S. (William Samuel)

The doctor noticed all this as he followed Hatteras; his foot sank into a volcanic tufa, and the deposits of ashes, volcanic stones, etc., like the syenite and granite of Iceland.

From The Voyages and Adventures of Captain Hatteras by Riou, Edouard

Both syenite and diorite also occur as igneous rocks.

From Geology by Geikie, James