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

Word History

First Known Use

1963, in the meaning defined above

Time Traveler
The first known use of bioclast was in 1963

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Dictionary Entries Near bioclast

Cite this Entry

“Bioclast.” Dictionary, Merriam-Webster, Accessed 13 Apr. 2024.

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