1. fish having fleshy, lobed fins that contain bone and muscle structures, considered evolutionary ancestors of land vertebrates
Usage: zoological; plural form

Examples

• Lobefins are thought to be the ancestors of all land vertebrates.
• The coelacanth is one of the few surviving lobefins.
• Scientists study lobefins to understand the evolution from water to land.
• Fossil lobefins show the transition from fins to limbs.
• Modern lobefins include lungfish and coelacanths.
• The muscular fins of lobefins helped them move in shallow water.