Meaning: “lady of the water.”
The name is found in Tupi legend as the name of a type of mermaid creature. The Iara are believed to live in bodies of freshwater. When they know a man is near they sing in order to trap them. Once in her power, there is nothing that can stop a man from falling in love with the her. Usually they marry her and go live with the Iara in her underwater kingdom, until they die, and since the Iara is immortal, she goes back to the world to find another man to take as her husband.
According to one Tupi legend, Iara was a warrior woman and was considered the best warrior in her tribe. Her brothers became jealous of her and plotted to kill her in her sleep, but Iara learned of their plans before they could kill her so she ended up killing them. As punishment, her father sent her off to a lake where she was transformed into a mermaid, now known as a Iara, and became immortal.
Iara has become a fairly common female name in both Brazil and Argentina. She is currently the 36th most popular female name in Argentina, (2009).