fag-end vs tag end

fag-end

noun

  • last remnant 

  • The unsmoked end of a cigarette or cigar 

  • frayed end of a length of cloth or rope 

tag end

noun

  • Something left over. 

  • The very end. 

How often have the words fag-end and tag end occurred in a corpus of books? (source: Google Ngram Viewer )