tosher

Etymology 1
From 19th-century British thieves' cant +.

Noun

 * 1)  A thief who steals the copper siding from the bottoms of vessels, particularly in or along the Thames.
 * 2)  A scavenger of valuables lost in the sewers, particularly those of London during the Victorian Age.
 * 1)  A scavenger of valuables lost in the sewers, particularly those of London during the Victorian Age.

Etymology 2
See tosh.