The definition of micro is an extremely small thing.(adjective)
An example of micro is something unable to be seen with the naked eye; a micro dot.
Micro is defined as something very tiny.(noun)
An example of a micro is bacteria.
See micro in Webster's New World College Dictionary
Origin: Gr mikro- < mikros, small < IE *(s)meik-: see mica
See micro in American Heritage Dictionary 4
Origin: From micro-.
Origin: Greek mīkro-
Origin: , from mīkros, small.
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