micro-

1. a combining form with the meanings “small” (microcosm; microgamete), “very small in comparison with others of its kind” (microcassette; microlith), “too small to be seen by the unaided eye” (microfossil; microorganism), “dealing with extremely minute organisms, organic structures, or quantities of a substance” (microdissection; microscope), “localized, restricted in scope or area” (microburst; microhabitat), “(of a discipline) focusing on a restricted area” (microeconomics), “containing or dealing with texts that require enlargement to be read” (microfilm; microreader), “one millionth” (microgram).

combining form

1. small or minutemicrospore
2. involving the use of a microscopemicrography
3. indicating a method or instrument for dealing with small quantitiesmicrometer
4. (in pathology) indicating abnormal smallness or underdevelopmentmicrocephaly; microcyte Compare macro- (def. 2)
5. denoting 10 –6microsecond Symbol: μ

word-forming element meaning “small, microscopic; magnifying; one millionth,” from Latinized comb. form of Greek mikros “small, little, petty, trivial, slight” (see mica). pref.

1. Small:microblast.
2. Abnormally small:microcephaly.
3. Requiring or involving microscopy:microsurgery.
4. One-millionth (10-6):microliter.

1. A prefix that means: “small” (as in microorganism) or “one millionth” (as in microsecond).