despot

 
Pronunciation: /ˈdɛspɒt/

noun

  • a ruler or other person who holds absolute power, typically one who exercises it in a cruel or oppressive way.

Origin:

mid 16th century: from French despote, via medieval Latin from Greek despotēs 'master, absolute ruler'. Originally (after the Turkish conquest of Constantinople) the term denoted a minor Christian ruler under the Turkish empire. The current sense dates from the late 18th century