The Collaborative International Dictionary of English v.0.48:

Tin \Tin\, v. t. [imp. & p. p. Tinned; p. pr. & vb. n.
   Tinning.]
   To cover with tin or tinned iron, or to overlay with tin
   foil.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Tinning \Tin"ning\, n.
   1. The act, art, or process of covering or coating anything
      with melted tin, or with tin foil, as kitchen utensils,
      locks, and the like.
      [1913 Webster]

   2. The covering or lining of tin thus put on.
      [1913 Webster]

WordNet (r) 3.0 (2006):

tinning
    n 1: the application of a thin layer of soft solder to the ends
         of wires before soldering them; "careful tinning of the
         ends of wires results in a better joint when you solder
         them"
    2: the application of a protective layer of tin [syn: tinning,
       tin-plating]