psephite
/ˈsiːfaɪt/
noun
- A rock or sediment made up of pebbles or gravel-sized fragments.
- Ancient riverbeds often leave behind layers of psephite.
- The geologist identified the sample as a psephite because it contained many small pebbles.
- The construction crew dug through a thick deposit of psephite while building the foundation.
Synonyms