1. A type of armed combat in which the opposing troops fight from trenches that face each other
   "instead of the war ending quickly, it became bogged down in trench warfare"
    
2. A struggle (usually prolonged) between competing entities in which neither side is able to win
   "the hope that his superior campaigning skills would make a difference evaporated in the realization that electioneering had become a form of trench warfare"

Type of: armed combat, combat, war, warfare

Encyclopedia: Trench warfare