1. [n]  a conical fishnet dragged through the water at great depths
2. [n]  a long fishing line with many shorter lines and hooks attached to it (usually suspended between buoys)
3. [v]  fish with trawlers

TRAWL is a 5 letter word that starts with T.

1. \Trawl\, v. i. [OF. trauler, troller, F. tr[^o]ter, to
   drag about, to stroll about; probably of Teutonic origin. Cf.
   {Troll}, v. t.]
   To take fish, or other marine animals, with a trawl.
   
   

2. \Trawl\, n.
   1. A fishing line, often extending a mile or more, having
      many short lines bearing hooks attached to it. It is used
      for catching cod, halibut, etc.; a boulter. [U. S. &
      Canada]
   
   2. A large bag net attached to a beam with iron frames at its
      ends, and dragged at the bottom of the sea, -- used in
      fishing, and in gathering forms of marine life from the
      sea bottom.
   
   

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