bio·​clast | \ ˈbī-(ˌ)o-ˌklast How to pronounce bioclast (audio) \
plural bioclasts

Definition of bioclast

: a fragment of biological origin (such as a shell fragment or fossil) occurring in sedimentary rock You can have fabrics full of bioclasts—fragments of organic origin, such as bits of plants or clamshells—and you can classify the kinds of mineral grains, their size and distribution.— Karen Chin, quoted in Discover, June 1996

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First Known Use of bioclast

1963, in the meaning defined above

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The first known use of bioclast was in 1963

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Cite this Entry

“Bioclast.” Dictionary, Merriam-Webster, Accessed 4 Aug. 2020.

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