a fossil so small that it can be studied and identified only with a microscope.
Origin of microfossil
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
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
A microscopic fossil, as of a pollen grain or unicellular organism.
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