Bathtub Gin Meaning

(idiomatic) Gin or a similar alcoholic beverage which is of very poor quality, as if made by a homebrewer in a bathtub.

Example: 1936 June 14, "‘Dates as Usual’," Milwaukee Journal, p. 2 (retrieved 31 July 2013):
  Part of Dallman's "Three Blind Mice" parody follows:
  They called us donkey-braying cranks
  But all they gave to win our thanks
  Was bathtub gin and busted banks
  For twelve long years.
1984 Dec. 30, Alvin Klein, "‘Brown Sugar’ Done to a Bubbling Turn" (theatre review), New York Times (retrieved 31 July 2013):
  A 1976 Broadway hit, "Bubbling Brown Sugar" recreates the night life of the 1920's - when they drank "scotch in teacups" and bathtub gin.
2008 Dec. 5, "Top 10 Prohibition Tales: Mortal Moonshine," Time:
  It wasn't just the violent Prohibition-era gang wars that were dangerous to Americans drinking homemade moonshine and bathtub gin.