slicker vs smooth operator

slicker

noun
  • A person who is perceived as clever, urbane and possibly disreputable. (abbreviation of city slicker.) 

  • A waterproof coat or jacket. 

  • A symmetrical knife with a handle at each end, used for burnishing leather. 

  • A brush for grooming a cat and removing loose fur. 

  • A swindler or conman. 

  • A curved tool for smoothing the surfaces of a mould after the withdrawal of the pattern. 

  • A two-handled tool for finishing concrete or mortar; a darby. 

  • One who or that which slicks. 

verb
  • To slither, as on a slick surface. 

  • To con or hoodwink. 

  • To use a slicker on. 

  • To smooth or slick. 

  • To spread mashed manure on fields as a form of fertilization. 

smooth operator

noun
  • A skillful, manipulative person, con artist, or clever scoundrel. 

  • A person who accomplishes tasks with efficiency and grace, especially one with verbal skills who is persuasive in interpersonal relationships, negotiation, etc. 

How often have the words slicker and smooth operator occurred in a corpus of books? (source: Google Ngram Viewer )