As nouns the difference between dorado and mahimahi

is that dorado is Coryphaena hippurus, the mahi-mahi or dolphin, a species of fish with a dorsal fin that runs the length of the body, also known for iridescent coloration while mahimahi is an alternative spelling of mahi-mahi.

As a proper noun Dorado

is a small constellation of the southern sky, said to resemble a goldfish or swordfish. It lies between the constellations Pictor and Reticulum, and is notable for containing most of the Large Magellanic Cloud.