laccolith

noun

lac·co·lith ˈla-kə-ˌlith

: a mass of igneous rock that is intruded between sedimentary beds and produces a domical bulging of the overlying strata

laccolithic

ˌla-kə-ˈli-thik

adjective

Word History

Etymology

Greek lakkos pond, reservoir + English -lith — more at lake

First Known Use

1880, in the meaning defined above

Time Traveler

The first known use of laccolith was in 1880

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laccol

laccolith

lac dye

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Style

“Laccolith.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/laccolith. Accessed 7 Jul. 2026.

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laccolith

noun

Word History

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