1. An anatomical or biological enlargement, extension, or projection located on the dorsal (back) surface of an organism or structure
The fish displayed a prominent dorsal expansion along its back.
O peixe exibia uma expansão dorsal proeminente ao longo de suas costas.
2. In zoology, an outgrowth or flattened extension of the dorsal fin or body wall in aquatic animals
The cetacean's dorsal expansion helps with temperature regulation.
A expansão dorsal do cetáceo ajuda na regulação da temperatura.
3. In botany or mycology, a dorsal structure or membrane that extends outward
The fungus showed a distinctive dorsal expansion under the microscope.
O fungo mostrou uma expansão dorsal distintiva sob o microscópio.