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).
small or minute: microspore
involving the use of a microscope: micrography
indicating a method or instrument for dealing with small quantities: micrometer
(in pathology) indicating abnormal smallness or underdevelopment: microcephaly, microcyte Compare macro- (sense 2)
denoting 10–6: microsecond, μ
word-forming element meaning “small, microscopic; magnifying; one millionth,” from Latinized comb. form of Greek mikros “small, little, petty, trivial, slight” (see mica).
micro- or micr-
A prefix that means: “small” (as in microorganism) or “one millionth” (as in microsecond).
microabscess mi·cro·ab·scess (mī’krō-āb’sěs’) n. A very small circumscribed collection of white blood cells in solid tissues.
microadenoma mi·cro·ad·e·no·ma (mī’krō-ād’n-ō’mə) n. A very small pituitary adenoma thought to cause hypersecretion syndromes.
microaerophil mi·cro·aer·o·phil (mī’krō-âr’ə-fĭl’) or mi·cro·aer·o·phile (-fīl’) n. An aerobic bacterium that survives in environments having a lower concentration of oxygen than is present in air. adj. Of, relating to, or behaving like such an organism. mi’cro·aer’o·phil’ic (-fĭl’ĭk) adj.
/ˌmaɪkrəʊˈɛərəʊˌfaɪl/ noun 1. an organism, esp a bacterium, that thrives in an environment low in oxygen