Emily Dickinson Lexicon

TRENCH, v.t. [Fr. trancher, to cut; It. trincea, a trench; trinciare, to cut; Sp. trincar, trinchear; Arm. troucha; W. tryçu.]

1. To cut or dig, as a ditch, a channel for water, or a long hollow in the earth. We trench land for draining. [This is the appropriate sense of the word.]
2. To fortify by cutting a ditch and raising a rampart or breast-work of earth thrown out of the ditch. [In this sense, entrench is more generally used.]
3. To furrow; to form with deep furrows by plowing.
4. To cut a long gash. [Not in use.] Shak.