Source : Webster's Revised Unabridged Dictionary (1913)

Trench \Trench\, n. [OE. trenche, F. tranch['e]e. See {Trench},
   v. t.]
   1. A long, narrow cut in the earth; a ditch; as, a trench for
      draining land. --Mortimer.

   2. An alley; a narrow path or walk cut through woods,
      shrubbery, or the like. [Obs.]

            In a trench, forth in the park, goeth she.
                                                  --Chaucer.

   3. (Fort.) An excavation made during a siege, for the purpose
      of covering the troops as they advance toward the besieged
      place. The term includes the parallels and the approaches.

   {To open the trenches} (Mil.), to begin to dig or to form the
      lines of approach.

   {Trench cavalier} (Fort.), an elevation constructed (by a
      besieger) of gabions, fascines, earth, and the like, about
      half way up the glacis, in order to discover and enfilade
      the covered way.

   {Trench plow}, or {Trench plough}, a kind of plow for opening
      land to a greater depth than that of common furrows.

Trench \Trench\, v. t. [imp. & p. p. {Trenched}; p. pr. & vb. n.
   {Trenching}.] [OF. trenchier to cut, F. trancher; akin to Pr.
   trencar, trenchar, Sp. trinchar, It. trinciare; of uncertain
   origin.]
   1. To cut; to form or shape by cutting; to make by incision,
      hewing, or the like.

            The wide wound that the boar had trenched In his
            soft flank.                           --Shak.

            This weak impress of love is as a figure Trenched in
            ice, which with an hour's heat Dissolves to water,
            and doth lose its form.               --Shak.

   2. (Fort.) To fortify by cutting a ditch, and raising a
      rampart or breastwork with the earth thrown out of the
      ditch; to intrench. --Pope.

            No more shall trenching war channel her fields.
                                                  --Shak.

   3. To cut furrows or ditches in; as, to trench land for the
      purpose of draining it.

   4. To dig or cultivate very deeply, usually by digging
      parallel contiguous trenches in succession, filling each
      from the next; as, to trench a garden for certain crops.

Trench \Trench\, v. i.
   1. To encroach; to intrench.

            Does it not seem as if for a creature to challenge
            to itself a boundless attribute, were to trench upon
            the prerogative of the divine nature? --I. Taylor.

   2. To have direction; to aim or tend. [R.] --Bacon.

   {To trench at}, to make trenches against; to approach by
      trenches, as a town in besieging it. [Obs.]

            Like powerful armies, trenching at a town By slow
            and silent, but resistless, sap.      --Young.

Source : WordNet®

trench
     n 1: a ditch dug as a fortification having a parapet of the
          excavated earth
     2: a long steep-sided depression in the ocean floor [syn: {deep},
         {oceanic abyss}]
     3: any long ditch cut in the ground
     v 1: impinge or infringe upon; "This impinges on my rights as an
          individual"; "This matter entrenches on other domains"
          [syn: {impinge}, {encroach}, {entrench}]
     2: fortify by surrounding with trenches; "He trenched his
        military camp"
     3: cut or carve deeply into; "letters trenched into the stone"
     4: set, plant, or bury in a trench; "trench the fallen
        soldiers"; "trench the vegetables"
     5: cut a trench in, as for drainage; "ditch the land to drain
        it"; "trench the fields" [syn: {ditch}]
     6: dig a trench or trenches; "The National Guardsmen were sent
        out to trench"