noun Geology.

a mass of igneous rock formed from magma that did not find its way to the surface but spread laterally into a lenticular body, forcing overlying strata to bulge upward.

Nearby words

  1. lacan,
  2. lacan, jacques,
  3. laccadive islands,
  4. laccadive, minicoy, and amindivi islands,
  5. laccolite,
  6. laccolitic,
  7. lace,
  8. lace bug,
  9. lace glass,
  10. lace into

Also lac·co·lite [lak-uh-lahyt] /ˈlæk əˌlaɪt/.

Origin of laccolith

1875–80; < Greek lákko(s) pond + -lith

Related formslac·co·lith·ic, lac·co·lit·ic [lak-uh-lit-ik] /ˌlæk əˈlɪt ɪk/, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for laccolith


laccolite (ˈlækəˌlaɪt)


a dome-shaped body of igneous rock between two layers of older sedimentary rock: formed by the intrusion of magma, forcing the overlying strata into the shape of a domeSee lopolith
Derived Formslaccolithic or laccolitic (ˌlækəˈlɪtɪk), adjective

Word Origin for laccolith

C19: from Greek lakkos cistern + -lith

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Science definitions for laccolith



A body of igneous rock intruded between layers of sedimentary rock, resulting in uplift. Laccoliths are usually plano-convex in cross-section, having a flat bottom and a convex top, and are roughly circular in plan. They are usually connected to a dike and are typically up to 8 km (5 mi) in diameter and tens to hundreds of meters thick. See illustration at batholith.
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