Voivod (also spelled vajda, vojvod, vojvoda, wojwod, wojewoda, voivode, voivoda, Voievod, Russian: воевода, voyevoda) is a term of Slavic etymology denoting a military commander, literally, a warlord, (from "voi", plural "voie" - "warrior(s)", and "vodit'" - "to lead"). Later the term came to denote the governor of a province. A territory over which a voivod rules is called a voivodship (see Vojvodina).
Voyevoda is Slavic word appropriate latin dux or German Heerzog.
The leader of armies at first chosen on a case of war, and from the end of 8 centuries became a constant military leader, the governor at slavic peoples.
The word Voyevoda was replaced with word the governor at the end of 18th century.