Definition of exine in English:


Pronunciation /ˈekˌsēn//-ˌsīn/


  • The decay-resistant outer coating of a pollen grain or spore. It typically bears a highly characteristic surface pattern that is used in palynology.

    • ‘A few grains were seen which had shed the exine and released a circular microgametophyte, although the actual process was not observed.’
    • ‘This study concentrates on these parameters using purified exines (sporopollenin capsules) prepared from pine pollen, which consist of a central capsule and two lateral sacci.’
    • ‘The final activity of these cells is to deposit their remaining cell contents onto the developing pollen exine, with the only remaining identifiable organelles at this stage being the mitochondria.’
    • ‘Short elongated elements occur on the orbicule wall, similar to those present on the pollen exine.’
    • ‘Orbicules may be attached to the exine of the pollen grains.’


Late 19th century: perhaps from ex- out + Greek is, in- fiber.