too small to be seen through a microscope.
Sometimes sub·mi·cro·scop·i·cal.Related formssub·mi·cro·scop·i·cal·ly, adverb
Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
Examples from the Web for submicroscopic
Historical Examples of submicroscopic
In any case, a microscope would have done Brown little good in trying to detect the submicroscopic beings of the Rell.
These colloid substances have a submicroscopic or micellian structure; they are web-like, porous and absorb water eagerly.
Very few, if any, higher life forms existed that did not have some sort of submicroscopic parasite afflicting them.
British Dictionary definitions for submicroscopic
Derived Formssubmicroscopically, adverb
too small to be seen through an optical microscope
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
submicroscopic in Medicine
Too small to be visible under the most powerful optical microscope.
The American Heritage® Stedman's Medical Dictionary
Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.