money tree vs slag

money tree

noun
  • The jade plant, Crassula ovata. 

  • A cheap tree sculpture, decorated with currency, used as a raffle prize because it would be illegal to offer a cash prize. 

  • An imaginary tree from which money can be plucked. See money doesn't grow on trees. 

  • The cocoa tree, Theobroma cacao. 

  • A kind of holy tree believed to bring money and good fortune. 

  • The Malabar chestnut, Pachira aquatica. 

  • A miniature tree sculpture decorated with currency, often used as a raffle prize or a gift. 

slag

noun
  • Scoria associated with a volcano. 

  • Scum that forms on the surface of molten metal. 

  • A prostitute, or a woman who acts like one; a slut. 

  • Waste material from a mine. 

  • Hard aggregate remaining as a residue from blast furnaces, sometimes used as a surfacing material. 

  • Impurities formed and separated out when a metal is smelted from ore; vitrified cinders. 

  • A contemptible person, a scumbag. 

verb
  • To spit. 

  • To become slag; to agglomerate when heated below the fusion point. 

  • To reduce to slag. 

  • To talk badly about; to malign or denigrate (someone). 

  • To produce slag. 

How often have the words money tree and slag occurred in a corpus of books? (source: Google Ngram Viewer )