noun[mass noun] Geology
- Rock fragments and particles ejected by a volcanic eruption.More example sentences
- Any such lateral motions could contribute to the absence or thinness of distal marine tephra layers on submarine high points or steep slopes.
- Two types of tephra fallout deposits have been observed.
- Some reports are stating that that tephra rim could collapse later this year.
1940s: from Greek, literally 'ash, ashes'.
More definitions of tephraDefinition of tephra in:
- The US English dictionary