la·​har | \ ˈlä-ˌhär How to pronounce lahar (audio) \

Definition of lahar

: a moving fluid mass composed of volcanic debris and water

Examples of lahar in a Sentence

Recent Examples on the Web Nuts, fruits, leaves and twigs were caught in the lahar, and their fossils can be seen in the Clarno formation along the Trail of Fossils. Washington Post, 4 Dec. 2020 The broad forested area in the foreground is underlain by many layers of volcanic deposits, chiefly lahars and pyroclastic flows generated from past eruptions of Mount St. Helens. Mahita Gajanan, Time, 6 June 2018 Lava began flowing out of the volcano and down toward the mountain’s flank and across homes and roads around 4 p.m. Dramatic video showed a fast-moving lahar slamming into a bridge on a highway between Sacatepequez and Escuintla. Ryan Gaydos, Fox News, 2 Oct. 2018 Seattle is probably safely out of reach of any future volcanic lahars, Moran said. The Seattle Times,, 8 May 2018 A few days later, rainstorms caused lahars, or ashen mudslides, which damaged the areas further. Lila Thulin, Smithsonian, 6 Sep. 2019 Also of concern is the potential for what are known as lahars, or flows of debris. Maya Wei-haas, Smithsonian, 19 Jan. 2018 The projected paths of lahars cover communities in the Stillaguamish and Skagit valleys. Kari Bray, The Seattle Times, 19 Aug. 2018 Orting is the town most vulnerable to lahar damage from Mount Rainier, according to the U.S. Geological Survey. Bradford Betz, Fox News, 13 May 2018 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'lahar.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of lahar

1929, in the meaning defined above

History and Etymology for lahar


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Dictionary Entries Near lahar

Lahaina disease



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Cite this Entry

“Lahar.” Dictionary, Merriam-Webster, Accessed 3 Jul. 2022.

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