Dorado is a Southern Hemisphere constellation otherwise known as the Swordfish. It is one of twelve constellations created around 1597 by Petrus Plancius (Wikipedia) from observations by the Dutch navigators Pieter Dirkszoon Keyser and Frederick de Houtman. Dorado remains one of the 88 modern constellations defined by the International Astronomical Union (Wikipedia).
Dorado (abbrev. = Dor; genitive = Doradus) covers 179 square degrees or 0.43% of the celestial sphere making it the 72nd largest constellation. It contains 29 stars brighter than apparent magnitude 6.5, the brightest star being Alpha Doradus.