The Collaborative International Dictionary
Clastic \Clas"tic\, a. [Gr. ? br?, fr. ? to break.]
Pertaining to what may be taken apart; as, clastic anatomy (of models).
(Min.) Fragmental; made up of brok? fragments; as, sandstone is a clastic rock.
Douglas Harper's Etymology Dictionary
"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- (1) "to strike" (see holt).
Wiktionary
a. 1 made up of parts that are easily removable. 2 (context geology of rock English) made from fragments of pre-existing rocks.
WordNet
adj. of or belonging to or being a rock composed of fragments of older rocks (e.g., conglomerates or sandstone)
capable of being taken apart; "the professor had a clastic model of the human brain"
Wikipedia
Usage examples of "clastic".
At the very edge of the ruined city on its south side, the land fell away quickly in what had once been clastic slumps of silty clay, fanning out onto the old bed of the harbour.
The Gebel el Dist member is typically described as “made up of fine-grained, well-bedded, ferruginous [iron-rich] clastics [grainy rock] carrying a large number of fossils including vertebrates in the lower levels and an assortment of oysters and other fossils in middle and upper layers.