The name Majungasaurus is derived from the words " Majunga" , which is a district of Madagascar where they found the dinosaur, and " tholus" , which means dome in Latin.

玛君龙的名字来自两个词语，其一是“马任加”就是发现这种恐龙的马达加斯加的一个行政区名，另一个词语“tholus”，拉丁文意义是穹顶。