- any chiefly marine protozoan of the sarcodinian order Foraminifera, typically having a linear, spiral, or concentric shell perforated by small holes or pores through which pseudopodia extend.
Origin of foraminifer
Also called fo·ram·i·nif·er·an [fuh-ram-uh-nif-er-uh n] /fəˌræm əˈnɪf ər ən/, foram.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
C19: from New Latin, from foramen + -fer
- Any of various chiefly marine protozoans of the order Foraminiferida or Foraminifera, having a body enclosed by a shell called a test and making up an important constituent of plankton. Perforations in a foraminiferan's test allow the protrusion of numerous long extensions (pseudopods), which form a net used to trap food. The tests of foraminiferans grow throughout the organism's life, and can exceed 5 cm (2 inches) in diameter. The tests of dead organisms form ooze found on the ocean floor. Extinct foraminiferans are important index fossils.
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