isobaric

adj. pertaining to an isobar or isobars, of a line on a weather map or chart that connects areas of equal barometric pressure (Meteorology)

isobaric (meaning of the same weight or pressure) may refer to:in thermodynamics, an isobaric process, i.e. one that is carried out at constant pressure;in mass spectrometry, ions with the same mass, e.g. isobaric peptides, namely peptides with the same molecular weight.isobaric speakers have a loudspeaker design where two drive units are mounted in tandem.
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(a.)
Denoting equal pressure; as, an isobaric line; specifically, of or pertaining to isobars.
  

Having constant pressure.