The Collaborative International Dictionary of English v.0.48:

Tinker \Tink"er\, v. t. [imp. & p. p. Tinkered; p. pr. & vb.
   n. Tinkering.]
   To mend or solder, as metal wares; hence, more generally, to
   mend.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Tinkering \Tink"er*ing\, n.
   The act or work of a tinker.
   [1913 Webster]