noun (used with a plural verb)
clastic volcanic material, as scoria, dust, etc., ejected during an eruption.
Origin of tephra
First recorded in 1960–65, tephra is from the Greek word téphra (singular) ashes
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
mainly US solid matter ejected during a volcanic eruption
Word Origin for tephra
C20: Greek, literally: ashes
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
Solid matter, such as ash, dust, and cinders, that is ejected into the air by an erupting volcano. Tephra is a general term for all pyroclastic materials ejected from a volcano.
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