The Collaborative International Dictionary of English v.0.48:

Tanner \Tan"ner\, n.
   One whose occupation is to tan hides, or convert them into
   leather by the use of tan.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Tanner \Tan"ner\, n. [Etym. uncertain.]
   A sixpence. [Slang, Eng.]
   [Webster 1913 Suppl.]

WordNet (r) 3.0 (2006):

tanner
    n 1: a small coin of the United Kingdom worth six pennies; not
         minted since 1970 [syn: sixpence, tanner]
    2: a craftsman who tans skins and hides