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See also: Isobar


English Wikipedia has an article on:
Isobar Map (PSF)

Alternative forms[edit]


From Ancient Greek ἴσος (ísos, equal) + βάρος (báros, weight)


isobar (plural isobars)

  1. (meteorology) A line drawn on a map or chart connecting places of equal or constant pressure.
  2. (nuclear physics) Either of two nuclides of different elements having the same mass number.
  3. (thermodynamics) A set of points or conditions at constant pressure.

Usage notes[edit]

  • (meteorology):
    In meteorology, the term isobar most often refers to a line drawn through connected points of equal atmospheric pressure on a given reference surface — such as a constant height surface (notably mean-sea-level on surface charts), the vertical plane of a synoptic cross section, or a layer of the air unaffected by surface heating or cooling. The pattern of isobars has always been a main feature of surface chart analysis. (See Wikipedia-logo-v2.svg Surface weather analysis on Wikipedia.Wikipedia ) Until recently it was standard procedure to draw isobars at 3-millibar intervals. However, the advent of constant pressure charts for upper-air analysis has brought about the use of 4-millibar intervals to simplify the conversion from surface isobars to 1,000-millibar contour lines.


The translations below need to be checked and inserted above into the appropriate translation tables, removing any numbers. Numbers do not necessarily match those in definitions. See instructions at Wiktionary:Entry layout § Translations.

See also[edit]




isobar (neuter isobart, plural and definite singular attributive isobare)

  1. (thermodynamics) isobaric



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isobar (not comparable)

  1. isobaric


Further reading[edit]