compliment vs flatter

compliment

verb
  • To pay a compliment (to someone); to express a favourable opinion (of someone). 

noun
  • An expression of praise, congratulation, or respect. 

  • Complimentary language; courtesy, flattery. 

flatter

verb
  • To compliment someone, often (but not necessarily) insincerely and sometimes to win favour. 

  • To enhance someone's vanity by praising them. 

  • To encourage or cheer someone with (usually false) hope. 

  • To portray someone to advantage. 

noun
  • Someone who flattens, purposely or accidently. Also flattener. 

  • Someone who lives in a rented flat. 

  • A type of set tool used by blacksmiths. 

  • A flat-faced fulling hammer. 

  • A drawplate with a narrow, rectangular orifice, for drawing flat strips such as watch springs. 

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