1. Biology. breaking up into fragments or separate portions; dividing into parts.
  2. pertaining to an anatomical model made up of detachable pieces.
  3. Geology. noting or pertaining to rock or rocks composed of fragments or particles of older rocks or previously existing solid matter; fragmental.

Origin of clastic

1870–75; < Greek klastós broken in pieces (klas- variant stem of klân to break + -tos verbal adjective suffix) + -ic
Related formsnon·clas·tic, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Examples from the Web for clastic

Historical Examples of clastic

British Dictionary definitions for clastic


  1. (of sedimentary rock, etc) composed of fragments of pre-existing rock that have been transported some distance from their points of origin
  2. biology dividing into partsa clastic cell
  3. able to be dismantled for study or observationa clastic model of the brain

Word Origin for clastic

C19: from Greek klastos shattered, from klan to break
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for clastic

"consisting of broken pieces," 1875, in geology, from Latinized form of Greek klastos "broken in pieces," from klan, klaein "to break," from PIE *kla-, variant of root *kel- "to strike."

Online Etymology Dictionary, © 2010 Douglas Harper

clastic in Medicine


  1. Breaking up into pieces or exhibiting a tendency to break or divide.
  2. Separable into parts or having removable sections, as an anatomical model.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.

clastic in Science


  1. A rock fragment or grain resulting from the breakdown of larger rocks.
Related formsclastic adjective (klăstĭk)
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.