Source : Webster's Revised Unabridged Dictionary (1913)

Pleach \Pleach\, v. t. [imp. & p. p. {Pleached}; p. pr. & vb. n.
   {Pleaching}.] [Cf. OF. plaissier to bend, and also F. plisser
   to plait, L. plicare, plicitum, to fold, lay, or wind
   together. Cf. {Plash} to pleach.]
   To unite by interweaving, as branches of trees; to plash; to
   interlock. ``The pleached bower.'' --Shak.

Source : WordNet®

pleach
     v 1: form or weave into a braid or braids; "braid hair" [syn: {braid}]
          [ant: {unbraid}]
     2: interlace the shoots of; "pleach a hedge" [syn: {plash}]