isobar

noun

iso·​bar ˈī-sə-ˌbär How to pronounce isobar (audio)
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

Illustration of isobar
  • isobar 1

Examples of isobar in a Sentence

Recent Examples on the Web Trying to predict the unpredictable is why meteorologists often wind up at the isobar after work. Star Tribune, 15 July 2021 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. Jeff Halverson, Washington Post, 5 Mar. 2018 The next image shows the incredible pressure gradient (change in pressure over distance, revealed by contour lines called isobars). Jeff Halverson, Washington Post, 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. Jeff Halverson, Washington Post, 31 Aug. 2017 Dear Tom, What determines how isobars are drawn on weather maps? Tom Skilling, chicagotribune.com, 13 May 2017 Dear Tom, What determines how isobars are drawn on weather maps? Tom Skilling, chicagotribune.com, 13 May 2017 Isobars help the meteorologist locate frontal boundaries because fronts are located in troughs of low pressure. Tom Skilling, chicagotribune.com, 13 May 2017

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'isobar.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

International Scientific Vocabulary is- + -bar (from Greek baros weight); akin to Greek barys heavy — more at grieve

First Known Use

circa 1864, in the meaning defined at sense 1

Time Traveler
The first known use of isobar was circa 1864

Dictionary Entries Near isobar

Cite this Entry

“Isobar.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/isobar. Accessed 19 Mar. 2024.

Kids Definition

isobar

noun
iso·​bar ˈī-sə-ˌbär How to pronounce isobar (audio)
: a line drawn on a map to indicate areas having the same atmospheric pressure at a given time or for a given period
isobaric
ˌī-sə-ˈbär-ik
-ˈbar-
adjective

Medical Definition

isobar

noun
iso·​bar ˈī-sə-ˌbär How to pronounce isobar (audio)
: one of two or more atoms or elements having the same atomic weights or mass numbers but different atomic numbers

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