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microfossil

[mahy-kroh-fos-il]
noun
  1. a fossil so small that it can be studied and identified only with a microscope.
Compare macrofossil.

Origin of microfossil

First recorded in 1920–25; micro- + fossil
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for microfossil

microfossil

noun
  1. a fossil generally less than 0.5 millimetre in size, such as a protozoan, bacterium, or pollen grain
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
microfossil in Science

microfossil

[mī′krō-fŏs′əl]
  1. A microscopic fossil, as of a pollen grain or unicellular organism.
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