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Micro-
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Look up <i>micro-</i> in Wiktionary, the free dictionary. <p> <i>Micro</i> (<a href="/facts/Greek_letter/1cHwB8Dg">Greek letter</a> μ, <a href="/facts/Mu_(letter)/j1MMkE2w">mu</a>, non-<a href="/facts/Italic_type/BECCTMng">italic</a>) is a <a href="/facts/Metric_prefix/Y2MzkaeL">unit prefix</a> in the <a href="/facts/Metric_system/to24H0YK">metric system</a> denoting a factor of one <a href="/facts/Millionth/eakBCzTK">millionth</a> (10-6). It comes from the <a href="/facts/Ancient_Greek/LIK7NlUh">Greek</a> word μικρός (<i>mikrós</i>), meaning "small". </p><p>It is the only <a href="/facts/International_System_of_Units/S7YLglNz">SI</a> prefix which uses a character not from the <a href="/facts/Latin_alphabet/pqWVHpBz">Latin alphabet</a>. In <a href="/facts/Unicode/DDu3MfPV">Unicode</a>, the symbol is represented by U+03BC μ GREEK SMALL LETTER MU or the legacy symbol U+00B5 µ MICRO SIGN. </p><p>When <a href="/facts/Latin_alphabet/pqWVHpBz">Latin</a> characters are not available, the letter "u" is sometimes used instead of "μ". The prefix "mc" is also commonly used; for example, "mcg" denotes a microgram. </p>