clastic

Meanings

1. 1adjectivenot comparabletechnicalspecialist

   Made up of broken pieces of older rock or mineral, as many sedimentary rocks are.

   Grammar: Used before a noun, as in 'clastic rock'; it is not used after 'very' or in comparisons.

   Patterns

   • clastic rock
   • clastic sediment
   • clastic sedimentary rock

   Sandstone is a clastic rock because it forms from grains of older rocks.

   The geologist explained that clastic sediments are built from fragments carried by water or wind.

   In this region, the cliffs are made of clastic material rather than limestone.

2. 2adjectivenot comparabletechnicalbiology

   In biology, describing a structure or model that breaks into separate pieces.

   Grammar: Used before a noun in scientific descriptions, as in 'clastic model'.

   Patterns

   • clastic model
   • clastic structure

   The researchers proposed a clastic model in which the shell breaks apart into distinct plates.

   Some anatomical models are described as clastic because their parts can be separated.

Common combinations

clastic rock

Shale and sandstone are common types of clastic rock.

clastic sediment

Rivers deposit clastic sediment at the bottom of the lake.

clastic material

The cliff is mostly clastic material from eroded mountains.

Synonyms and how they differ

fragmental

A general word meaning 'made of fragments'; 'clastic' is the precise geological term.

Opposites

Word family

clast noun

A single fragment or piece of older rock found in a sedimentary rock.

Commonly confused: clastic or elastic?

Practice

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