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iso·bar | \ ˈī-sə-ˌbär 
\
\Definition of isobar
1 : an imaginary line or a line on a map or chart connecting or marking places of equal barometric pressure
2 : one of two or more atoms or elements having the same atomic weights or mass numbers but different atomic numbers
Illustration of isobar
isobar 1
Examples of isobar in a Sentence
Recent Examples on the Web But the local pressure gradient was most intense along the New England coast, where isobars were extremely crowded together, driving 40 to 50 mph sustained winds.
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Jeff Halverson, Washington Post, "A mighty wind: Behind one of Washington’s worst-ever winter wind storms," 5 Mar. 2018 The next image shows the incredible pressure gradient (change in pressure over distance, revealed by contour lines called isobars).
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Jeff Halverson, Washington Post, "A mighty wind: Behind one of Washington’s worst-ever winter wind storms," 5 Mar. 2018 From the two figures above, note that the isobars became spread apart and fewer in number (the signature of weakening) and the eyewall’s intense ring of rain diminished significantly.
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Jeff Halverson, Washington Post, "Harvey’s two-step across Texas: The peculiar meteorology behind a U.S. rain record," 31 Aug. 2017 Dear Tom, What determines how isobars are drawn on weather maps?
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Tom Skilling, chicagotribune.com, "Ask Tom: What determines how isobars are drawn on weather maps?," 13 May 2017 Dear Tom,
What determines how isobars are drawn on weather maps?
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Tom Skilling, chicagotribune.com, "Ask Tom: What determines how isobars are drawn on weather maps?," 13 May 2017 Isobars help the meteorologist locate frontal boundaries because fronts are located in troughs of low pressure.
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Tom Skilling, chicagotribune.com, "Ask Tom: What determines how isobars are drawn on weather maps?," 13 May 2017
See MoreThese example sentences are selected automatically from various online news sources to reflect current usage of the word 'isobar.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
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More Definitions for isobar
isobar
nouniso·bar | \ ˈī-sə-ˌbär \
\Kids Definition of isobar
: a line on a map to indicate areas having the same atmospheric pressure
isobar
nouniso·bar | \ ˈī-sə-ˌbär \
\Medical Definition of isobar
: one of two or more atoms or elements having the same atomic weights or mass numbers but different atomic numbers
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Time Traveler for isobar
The first known use of isobar was circa 1864
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