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Webster 1913 Edition
Syenite
Sy′e-nite
,Noun.
 [L. 
Syenites 
(sc. lapis
), from Syene
, Gr. [GREEK].] (Min.) 
(a) 
Orig., a rock composed of quartz, hornblende, and feldspar, anciently quarried at Syene, in Upper Egypt, and now called 
granite
. (b) 
A granular, crystalline, ingeous rock composed of orthoclase and hornblende, the latter often replaced or accompanied by pyroxene or mica. Syenite sometimes contains nephelite (elaeolite) or leucite, and is then called 
nephelite (elaeolite) syenite 
or leucite syenite
.