milli- [MIL i], mille-, mill-, mili-
(Latin: thousand; a decimal prefix used in the international metric system for measurements; including, thousandth, thousandths)
In the metric [decimal] system, milli- denotes 1/1 000 of a unit, thousandth [U.S.] and thousandth part [U.K.]; 10-3 [0.001] The metric symbol for milli- is m.
multimillionaire
Someone with money or assets worth several millions in value.