Word Study
milli-
CIDE DICTIONARY
milli-, [From L. mille a thousand.].
A prefix denoting a thousandth part of ; as, millimeter, milligram, milliampère. [1913 Webster]
OXFORD DICTIONARY
milli-, comb. form a thousand, esp. denoting a factor of one thousandth.
Usage
Abbr.: m.
Etymology
L mille thousand
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