clast

American  

[klast] / klæst /

noun

1. a grain of sediment, silt, sand, gravel, etc., especially as a constituent fragment of a clastic rock formation, as distinguished from a chemical or biogenic component of such a formation.

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clast Scientific  

/ klăst /

1. A rock fragment or grain resulting from the breakdown of larger rocks.

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Etymology

Origin of clast

First recorded in 1950–55; probably back formation from clastic