isobar

 
Pronunciation: /ˈʌɪsə(ʊ)bɑː/

noun

  • 1 Meteorology a line on a map connecting points having the same atmospheric pressure at a given time or on average over a given period.
  • Physics a curve or formula representing a physical system at constant pressure.
  • 2 Chemistry each of two or more isotopes of different elements, with the same atomic weight.

Derivatives

isobaric

Pronunciation: /-ˈbarɪk/
adjective

Origin:

mid 19th century: from Greek isobaros 'of equal weight', from isos 'equal' + baros 'weight'