Definition of "isobar" []

• A line on a weather map connecting points of equal atmospheric pressure. Also called isopiestic. (noun)
• Any of two or more kinds of atoms having the same atomic mass but different atomic numbers. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "I call it “isotropic platting” after the “isobar”."
• "I took a quick glance at the barograph, and at the isobar chart of the day before."
• "The marine component includes the open sea between these islands up to limit of the isobar of 40 m depth."