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n. An SI/MKS unit of measure, the length of 1/1000 of a metre. Symbol: mm

n. a metric unit of length equal to one thousandth of a meter

"The move followed a trial run of the technology, known as millimetre-wave scanners, at the Kelowna, B.C., airport."

metric linear unit   

millimetric   

millimeter   

kilometer    millimeter   

centimetre    millimeter    light-year    parsec    37-mm    millimeters    88-mm    nanometer    millisecond    128-mm