n. The act of retrenching, lopping off, or pruning; the act of removing what is superfluous: as, retrenchment of words in a writing.n. The act of curtailing, reducing, or lessening; diminution; particularly, the reduction of outlay or expenses; economy.n. Milit.: An interior rampart or defensible line, comprising ditch and parapet, which cuts off a part of a fortress from the rest, and to which a garrison may retreat to prolong a defense, when the enemy has gained partial possession of the place.n. An intrenchment.n. Synonyms and Reduction, curtailment, abridgment.