1864, coined from Greek isos "equal" (see iso-) + baros "weight" (from PIE root *gwere- (1) "heavy"). Line connecting places with the same barometric pressure at the same time. Related: Isobaric.
-ism
ism
Ismailite
isness
iso-
isobar
isocephalic
isochromatic
isochronous
isocracy
isodynamic