Millibar

n. unit of atmospheric pressure equal to one thousand dynes per square centimeter

The bar (symbol bar), decibar (symbol dbar) and the millibar (symbol mbar, also mb) are units of pressure. They are not SI units, but they are accepted for use with the SI. The bar is still widely used in descriptions of pressure because it is about the same as atmospheric pressure.
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Noun
1. a unit of atmospheric pressure equal to one thousandth of a bar; "atmospheric pressure at sea level is 1013 millibars"
(hypernym) pressure unit
(part-holonym) bar

n. millibar, unit of atmospheric pressure equal to one thousand dynes per square centimeter

n. millibar, unit of atmospheric pressure equal to one thousand dynes per square centimeter