felt-tip pen vs highlighter

felt-tip pen

noun
  • A pen that holds quick-drying ink conveyed to a writing surface by means of a felt nib. 

highlighter

noun
  • A marker pen used to highlight text. 

  • That which highlights or emphasizes something. 

  • A cosmetic product that reflects light, used to emphasize the contours of the face etc. 

How often have the words felt-tip pen and highlighter occurred in a corpus of books? (source: Google Ngram Viewer )