Phacolith
/ˈfækəlɪθ/noun
A lens-shaped igneous intrusion emplaced along the hinge of a folded rock layer, usually an anticline or syncline.
Did you know?Its name combines Greek words for a lentil or lens and stone, echoing the ancient visual symbolism of concealed power taking shape beneath the surface.
Etymological Timeline
Ancient Greek
Greek
φακός (phakos)
“Lentil; lens-shaped object; sometimes a spot or freckle”
Ancient Greek
Greek
λίθος (lithos)
“Stone or rock”
19th Century
Scientific Greek
phaco- + -lith
“Technical combining forms meaning “lens” and “stone””
Late 19th–Early 20th Century
Geological English
phacolith
“A geological term for a lens-shaped intrusive body associated with a folded structure”
Modern English
English
phacolith
“A concordant igneous intrusion occupying the hinge zone of an anticline or syncline”
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