1. a line on a map connecting points of equal depth in a body of water, such as an ocean or lake
Usage: technical; cartography; oceanography

Examples

• The isobath marked on the nautical chart showed the 100-meter depth line.
• Oceanographers use isobaths to map the underwater topography of the continental shelf.
• The isobaths on this bathymetric map reveal a steep underwater canyon.
• Fishermen often follow isobaths because certain fish species prefer specific depths.
• The isobath pattern indicated a gradual slope toward the ocean trench.