microfossil

[ mahy-kroh-fos-il ]
/ ˌmaɪ kroʊˈfɒs ɪl /

noun

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. 2019

British Dictionary definitions for microfossils

microfossil

/ (ˈmaɪkrəʊˌfɒsəl) /

noun

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

Science definitions for microfossils

microfossil

[ mīkrō-fŏs′əl ]

A microscopic fossil, as of a pollen grain or unicellular organism.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.