Wordnet 3.0
NOUN (2)
1.
a struggle (usually prolonged) between competing entities in which neither side is able to win;
- Example: "the hope that his superior campaigning skills would make a difference evaporated in the realization that electioneering had become a form of trench warfare"2.
a type of armed combat in which the opposing troops fight from trenches that face each other;
- Example: "instead of the war ending quickly, it became bogged down in trench warfare"
WordNet (r) 3.0 (2006):
trench warfare
n 1: 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"
2: 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"