teph·​ra ˈte-frə How to pronounce tephra (audio)
: solid material ejected into the air during a volcanic eruption
especially : ash entry 2 sense 2b

Examples of tephra in a Sentence

Recent Examples on the Web Gas emissions and rock fragments ejected from the volcano into the air, known as tephra, were the primary hazards from the eruption, the observatory said. Alex Sundby, CBS News, 4 June 2024 Volcanoes are vents where lava, tephra, and steam erupt onto the Earth's surface. Lea Lane, Forbes, 29 Mar. 2024 Lava flows, hydrated mineral deposits as well as pyroclastic deposits made of volcanic particulate materials such as ash, cinders, pumice and tephra, occur in several areas within the structure’s perimeter. Michael Dorgan, Fox News, 15 Mar. 2024 First, explosive volcanic eruptions produce tephra, with is a bit of a catch-all for volcanic debris like ash, pumice, bombs, etc. Erik Klemetti, Discover Magazine, 30 May 2023 The tephra might seem like a bit of a surprise for an eruption that has produced abundant lava flows, but the powerful lava fountains that have occurred at the 4-5 vents of the eruption throw volcanic debris high into the air. Erik Klemetti, Discover Magazine, 28 Oct. 2021 In other parts of the world, the Grozny Group in the Kuril Islands had a small explosive eruption while a small tephra cone was seen growing in the Buoco Nuovo crater at Etna. Erik Klemetti, Discover Magazine, 3 Jan. 2013 However, the tephra used in the tomb's mortar contained much more potassium-rich leucite. Jennifer Ouellette, Ars Technica, 19 Apr. 2023 The sulfur and tephra of a large eruption can also rain down on Earth's poles, where they are preserved in layers of ice. David Bressan, Forbes, 3 May 2022

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'tephra.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


New Latin, from Greek, ashes; akin to Sanskrit dahati it burns — more at foment

First Known Use

circa 1944, in the meaning defined above

Time Traveler
The first known use of tephra was circa 1944

Dictionary Entries Near tephra

Cite this Entry

“Tephra.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tephra. Accessed 19 Jun. 2024.

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