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A rock fragment or grain resulting from the breakdown of larger rocks.
[From Greek klastos, broken, from klān, to break.]
(Minerals) a fragment of (sedimentary) rock broken off from a larger rock
a fragment of a clastic rock formation.
[1950–55; probably back formation from clastic]
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|Noun||1.||clast - (geology) a constituent fragment of a clastic rock|
geology - a science that deals with the history of the earth as recorded in rocks
clastic rock - (geology) a rock composed of broken pieces of older rocks
fragment - a piece broken off or cut off of something else; "a fragment of rock"