The first, unofficial, mention of "Amargasaurus" as a new genus of dinosaur was published by Bonaparte in the 1984 Italian book "Sulle Orme dei Dinosauri". Here, the species was designated as "Amargasaurus groeberi", honoring Pablo Groeber, which was changed into "Amargasaurus cazaui" in the official description published several years later. The official description, written in Spanish, was published in 1991 by Leonardo Salgado and Bonaparte in the Argentinian scientific journal "Ameghiniana". The name "Amargasaurus" alludes to the site of discovery, the La Amarga Arroyo. La Amarga is also the name of a nearby town, as well as the geologic formation the remains were recovered from. The word "amarga" is Spanish for "bitter", while "sauros" is Greek for "lizard". The one species ("A. cazaui") is named in honor of Luis Cazau, a geologist with the YPF oil company, which at the time was state-owned. In 1983, Cazau informed Bonaparte's team about the paleontological significance of the La Amarga Formation, leading to the discovery of the skeleton. One year later, Salgado and Jorge O. Calvo published a second paper focusing on the description of the skull.