prosauropod
noun
pro·sau·ro·pod prō-ˈsȯr-ə-ˌpäd 
: any of a group (Prosauropoda) of chiefly herbivorous Triassic dinosaurs that are probably ancestral to sauropods
Word History
Etymology
New Latin Prosauropoda, from pro- entry 1 + Sauropoda — more at sauropod
First Known Use
1941, in the meaning defined above