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

British Dictionary definitions for microfossil

microfossil
/ (ˈmaɪkrəʊˌfɒsəl) /

noun

a fossil generally less than 0.5 millimetre in size, such as a protozoan, bacterium, or pollen grain

Scientific definitions for microfossil

microfossil
[ mīkrō-fŏs′əl ]

A microscopic fossil, as of a pollen grain or unicellular organism.