retrench (v.1) Look up retrench at
1590s, "dig a new trench as a second line of defense," 1590s, probably a back-formation from retrenchment in the military sense. Related: Retrenched; retrenching.
retrench (v.2) Look up retrench at
"cut off, cut down, pare away" (expenses, etc.), 1620s, from obsolete French retrencher "to cut off, lessen, shorten" (Modern French retrancher, Old French retrenchier), from re- "back" (see re-) + Old French trenchier "to cut" (see trench). Related: Retrenched; retrenching.