Source : Webster's Revised Unabridged Dictionary (1913)

Leech \Leech\, n. [Cf. LG. leik, Icel. l[=i]k, Sw. lik boltrope,
   st[*a]ende liken the leeches.] (Naut.)
   The border or edge at the side of a sail. [Written also
   {leach}.]

   {Leech line}, a line attached to the leech ropes of sails,
      passing up through blocks on the yards, to haul the
      leeches by. --Totten.

   {Leech rope}, that part of the boltrope to which the side of
      a sail is sewed.