# isobar

> English word · Noun

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

## Etymology
From Ancient Greek ἴσος (ísos, “equal”) + βάρος (báros, “weight”), equivalent to iso- + bar-.

## Source
Compiled from Wiktionary via kaikki.org (CC BY-SA). Data vintage: 2026-05-06.
Canonical page: https://plainspell.com/en/word/isobar