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noun for·a·min·i·fer \ˌfȯr-ə-ˈmi-nə-fər, ˌfär-\

Definition of foraminifer

  1. :  any of an order (Foraminifera) of large chiefly marine rhizopod protozoans usually having calcareous shells that often are perforated with minute holes for protrusion of slender pseudopodia and form the bulk of chalk and nummulitic limestone


play \fə-ˌra-mə-ˈni-f(ə-)rəl; ˌfȯr-ə-mə-ˈni-, ˌfär-\ adjective

Illustration of foraminifer

Circa 1842

First Known Use of foraminifer

circa 1842

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