Satrap was the name given to the governors of the provinces of the ancient Median and Achaemenid (Persian) Empires and in several of their successors, such as the Sassanid Empire and the Hellenistic empires.
The word satrap is also often used in modern literature to refer to world leaders or governors who are heavily influenced by larger world superpowers or hegemonies and act as their surrogates.
Read more about Satrap: Etymology, Medo-Persian Satraps, Hellenistic Satraps, Parthian and Sassanian Satraps, Western Satraps, Satraps Today