Definition of "millibar" [millibar]

• A unit of atmospheric pressure equal to one thousandth (10-3) of a bar. Standard atmospheric pressure at sea level is about 1,013 millibars. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "'millibar'. 1 millibar = 1 / 1000 bar and 1 bar = 1 atm."
• "I was noticing that something had changed: the 500 millibar heights seemed to be getting higher."
• "At the same time, what meteorologists call the "1000-500 millibar thicknesses" had demonstrated a similar trend."