Definition of glochidium in English:


nounPlural glochidia

  • A parasitic larva of certain freshwater bivalve molluscs, which attaches itself by hooks and suckers to the fins or gills of fish.

    • ‘Unionid embryos spend the first stage of development in the marsupial portion of the female unionid's gills, where they develop into glochidia, the parasitic stage.’
    • ‘Zygotes develop within the mantle cavity and glochidia larvae are released in the early summer.’
    • ‘Many mussel species depend on specific species of fish to serve as hosts for mussel larvae, or glochidia.’
    • ‘The glochidia larvae of some freshwater mussels can be serious parasites of fish, and some marine bivalves bore through wood, causing damage to wooden ships, pilings, and other wood structures.’


Late 19th century: modern Latin, based on Greek glōkhis, glōkhid- ‘arrowhead’.