Meaning of RETRENCHMENT in English
noun the act or process of retrenching; as, the retrenchment of words in a writing.
2. retrenchment ·noun a work constructed within another, to prolong the defense of the position when the enemy has gained possession of the outer work; or to protect the defenders till they can retreat or obtain terms for a capitulation.
Webster English vocab. Английский словарь Webster. 2012