[en.trench] vt (1555) 1 a: to place within or surround with a trench esp. for defense b: to place (oneself) in a strong defensive position c: to establish solidly "~ed themselves in the business"
2: to cut into: furrow; specif: to erode downward so as to form a trench ~ vi 1: to dig or occupy a trench for defensive purposes
2: to enter upon or take over something unfairly, improperly, or unlawfully: encroach--used with on or upon -- en.trench.ment n