Definition of ejecta in English:


Pronunciation /əˈjektə/ /əˈdʒɛktə/

See synonyms for ejecta on

plural noun

Geology Astronomy
often treated as singular
  • Material that is forced or thrown out, especially as a result of volcanic eruption, meteoritic impact, or stellar explosion.

    ‘Melosh et al. proposed that wildfires were ignited by the thermal energy radiated by re-entering ejecta following the asteroid impact.’
    • ‘The stellar ejecta from the explosion initially trail behind the shock wave.’
    • ‘Impact ejecta deposits show a non-linear decrease in thickness with radial distance from the centre of the source crater.’
    • ‘The anomalous platinum group element geochemistry of the ejecta horizon suggests that the impactor was an asteroid.’
    • ‘Fresh impact craters are surrounded by fluidized ejecta patterns, likely produced by impact into subsurface water and ice.’
    • ‘Many craters are characterized by large lava-flow-like features that may represent molten ejecta flowing outward from the crater after the impact.’
    • ‘Behind the nucleus, a broad fan of impact ejecta, backlit by the Sun, spreads out into space.’
    • ‘You can also see the ejecta blanket, material that has been tossed out’ of the crater.’
    • ‘Their discovery of shocked quartz grains in a sandy layer in a Georgia kaolin mine documents the scatter of ejecta from the Chesapeake impact site.’
    • ‘From the impact ejecta volume, he calculated a crater size of around 150 to 200 meters.’
    • ‘The larger masses of molten glass remained near the effusive center; these were slower to solidify and commonly became strange agglomerations where bombarded by the rain of smaller ejecta.’
    • ‘The ejecta are still moving rapidly, however, and quickly sweep up surrounding matter to form a shell that slows down as mass gets accumulated, an action similar to that of a snowplow.’
    • ‘This could account for the finer ash layers in the quarry sequence being dominated by T2 ejecta.’


Late 19th century from Latin, ‘things thrown out’, neuter plural of ejectus ‘thrown out’, from eicere (see eject).