Definition of foraminifer in English:



  • A single-celled planktonic animal with a perforated chalky shell through which slender protrusions of protoplasm extend. Most kinds are marine, and when they die thick ocean-floor sediments are formed from their shells.

    See also globigerina
    • ‘Far from land in the deep sea, where little material comes from erosion of the land, the bottom sediment is made up mainly of shells of planktonic organisms, especially foraminifera.’
    • ‘These taxa consist of a broad array of organisms, including foraminifers, corals, bryozoans, mollusks, echinoderms, and fish.’
    • ‘It has been estimated that a large 150 micron wide shell of a foraminifer may take as long as 10 days to sink to the bottom of the ocean, whereas smaller ones would probably take much longer.’
    • ‘In a Swedish fjord sediment where G. pseudospinescens is the dominant foraminifer, the intracellular nitrate pool in this species accounted for 20% of the large, cell-bound, nitrate pool present in an oxygen-free zone.’
    • ‘The Gracisce packstones contain a rich foraminiferal assemblage, composed of larger and planktonic foraminifera along with authigenic glauconite.’


Mid 19th century: from Latin foramen, foramin- (see foramen) + -fer bearing (from ferre to bear).