A stygian place is extremely and unpleasantly dark, gloomy, and frightening.
Draconian rules and laws are extremely strict and harsh.
A stentorian voice is extremely loud and strong.
An authoritarian system, such as a government or military school, demands obedience from its subjects and allows them no individual say.
The adjective riparian refers or relates to the bank of a river or other natural waterway.
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