misname vs slag off

misname

verb
  • To call by a wrong name. 

  • To give an unsuitable or injurious name to; name incorrectly. 

noun
  • A wrong, unsuitable, misleading, or injurious name or designation; misnomer. 

slag off

verb
  • To talk insultingly to or about someone or something; usually one who is not present. 

  • To purify by melting and removing slag. 

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