Definition of osculum in English:


nounplural noun oscula/ˈäskyələ/ /ˈɑskjələ/

  • A large aperture in a sponge through which water is expelled.

    ‘Sponges will react by closing ostia or oscula, either because of direct physical stimulation or when suspended particles within the sponge are too large or highly concentrated.’
    • ‘In budding, aggregates of cells differentiate into small sponges that are released superficially or expelled through the oscula.’
    • ‘The hole closes and it is not until some days later that the sponge forms an osculum at its apical pole.’
    • ‘Syconoid sponges tend to be larger than asconoids and have a tubular body with a single osculum.’
    • ‘Spicules first appeared 2 days after release from the parent and an osculum was first seen in 9-day old settled juveniles.’



/ˈäskyələm/ /ˈɑskjələm/


Early 17th century from Latin ‘little mouth’.