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Milli-
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Look up <i>milli-</i> in Wiktionary, the free dictionary. <p><i>Milli</i> (symbol m) 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 thousandth (10−3). Proposed in 1793, and adopted in 1795, the prefix comes from the <a href="/facts/Latin/pM3Kge85">Latin</a> <i>mille</i>, meaning <i>one thousand</i> (the Latin plural is <i>milia</i>). Since 1960, the prefix is part of the <a href="/facts/International_System_of_Units/S7YLglNz">International System of Units</a> (SI). </p> <a href="/facts/Metric_prefix/Y2MzkaeL">SI prefixes</a><ul><li>v</li><li>t</li><li>e</li></ul><table><tbody><tr><th colspan="2">Prefix</th><th rowspan="2">Base 10</th><th rowspan="2"><a href="/facts/Decimal/7omfVNIM">Decimal</a></th><th rowspan="2">Adoption</th></tr><tr><th>Name</th><th>Symbol</th></tr><tr><td>quetta</td><td>Q</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">1030</a></td><td>1000000000000000000000000000000</td><td rowspan="2">2022</td></tr><tr><td>ronna</td><td>R</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">1027</a></td><td>1000000000000000000000000000</td></tr><tr><td>yotta</td><td>Y</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">1024</a></td><td>1000000000000000000000000</td><td rowspan="2">1991</td></tr><tr><td>zetta</td><td>Z</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">1021</a></td><td>1000000000000000000000</td></tr><tr><td>exa</td><td>E</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">1018</a></td><td>1000000000000000000</td><td rowspan="2">1975</td></tr><tr><td>peta</td><td>P</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">1015</a></td><td>1000000000000000</td></tr><tr><td>tera</td><td>T</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">1012</a></td><td>1000000000000</td><td rowspan="2">1960</td></tr><tr><td><a href="/facts/Giga-/vdrYKueB">giga</a></td><td>G</td><td><a href="/facts/1,000,000,000/Ij1fl5Q7">109</a></td><td>1000000000</td></tr><tr><td><a href="/facts/Mega-/rk32jTkD">mega</a></td><td>M</td><td><a href="/facts/1,000,000/RMGVIm1j">106</a></td><td>1000000</td><td>1873</td></tr><tr><td><a href="/facts/Kilo-/akxTdXyp">kilo</a></td><td>k</td><td><a href="/facts/1000_(number)/b3LRnMBK">103</a></td><td>1000</td><td rowspan="3">1795</td></tr><tr><td><a href="/facts/Hecto-/gVT7dDuw">hecto</a></td><td>h</td><td><a href="/facts/100/G6ynN9mT">102</a></td><td>100</td></tr><tr><td><a href="/facts/Deca-/IkCqeowc">deca</a></td><td>da</td><td><a href="/facts/10/pqN3l0vm">101</a></td><td>10</td></tr><tr><td>—</td><td>—</td><td><a href="/facts/1/d6SoCnze">100</a></td><td>1</td><td>—</td></tr><tr><td><a href="/facts/Deci-/umQMMcHW">deci</a></td><td>d</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">10−1</a></td><td>0.1</td><td rowspan="3">1795</td></tr><tr><td><a href="/facts/Centi-/UhDg8BJG">centi</a></td><td>c</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">10−2</a></td><td>0.01</td></tr><tr><td>milli</td><td>m</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">10−3</a></td><td>0.001</td></tr><tr><td><a href="/facts/Micro-/VXlL1EhM">micro</a></td><td>μ</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">10−6</a></td><td>0.000001</td><td>1873</td></tr><tr><td><a href="/facts/Nano-/hzbPWjMK">nano</a></td><td>n</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">10−9</a></td><td>0.000000001</td><td rowspan="2">1960</td></tr><tr><td>pico</td><td>p</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">10−12</a></td><td>0.000000000001</td></tr><tr><td>femto</td><td>f</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">10−15</a></td><td>0.000000000000001</td><td rowspan="2">1964</td></tr><tr><td>atto</td><td>a</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">10−18</a></td><td>0.000000000000000001</td></tr><tr><td>zepto</td><td>z</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">10−21</a></td><td>0.000000000000000000001</td><td rowspan="2">1991</td></tr><tr><td>yocto</td><td>y</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">10−24</a></td><td>0.000000000000000000000001</td></tr><tr><td>ronto</td><td>r</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">10−27</a></td><td>0.000000000000000000000000001</td><td rowspan="2">2022</td></tr><tr><td>quecto</td><td>q</td><td><a href="/facts/Orders_of_magnitude_(numbers)/uu2o1hk2">10−30</a></td><td>0.000000000000000000000000000001</td></tr><tr><td colspan="5">Notes</td></tr></tbody></table>