- 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. 2018
- mainly US solid matter ejected during a volcanic eruption
C20: Greek, literally: ashes
- 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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