1. A Late Triassic age, preceded by the Norian, followed by the Hettangian (Lias) and dated at 209.5–208 Ma ( Harland et al., 1989).
2. The name of the corresponding European stage, which is roughly contemporaneous with the Erchiao (China) and Otapirian (New Zealand). Some authors have placed the Rhaetian in the Jurassic. Others have questioned its status as a stage, suggesting that it should be a biostratigraphic zone within the underlying Norian.
"Rhaetian." A Dictionary of Earth Sciences. . Encyclopedia.com. (January 19, 2019). https://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/rhaetian
"Rhaetian." A Dictionary of Earth Sciences. . Retrieved January 19, 2019 from Encyclopedia.com: https://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/rhaetian