Microscopic

Microscopic is a term used to describe objects smaller than those that can easily be seen by the naked eye and which require a lens or microscope to see them clearly. By convention it is also used to describe classes of objects which are most commonly too small to see but of which some members are large enough to be observed with the eye. Such groups include the "Cladocera", planktonic green algae of which "Volvox" is readily observable, and the protozoa of which "Stentor" can be easily seen without aid.

Microscopic is also by association used to classify and describe the units and measurements relevant to very small objects. The antonym to microscopic is macroscopic

The units used to describe objects on a microscopic length scale are most commonly the Micrometer (µm) - one millionth of 1 metre, and smaller units.

Microscopic is also commonly used as a hyperbole in the English language to describe small objects of a class that would be expected to be bigger - as in "Her feet are microscopic!"