The Collaborative International Dictionary of English v.0.48:

Thole \Thole\, n. [Written also thowel, and thowl.] [OE.
   thol, AS. [thorn]ol; akin to D. dol, Icel. [thorn]ollr a fir
   tree, a young fir, a tree, a thole.]
   1. A wooden or metal pin, set in the gunwale of a boat, to
      serve as a fulcrum for the oar in rowing. --Longfellow.
      [1913 Webster]

   2. The pin, or handle, of a scythe snath.
      [1913 Webster]

   Thole pin. Same as Thole.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Thowel \Thow"el\, Thowl \Thowl\, n. [See Thole.] (Naut.)
   (a) A thole pin.
   (b) A rowlock.
       [1913 Webster]

             I would sit impatiently thinking with what an
             unusual amount of noise the oars worked in the
             thowels.                             --Dickens.
       [1913 Webster]