bookmark vs hashtag

bookmark

noun
  • A record of the address of a file or Internet page, serving as a shortcut to it. 

  • A strip of material used to mark a place in a book. 

  • A pointer found in a nonclustered index to a row in a clustered index or a table heap 

verb
  • To create a bookmark. 

hashtag

noun
  • A metadata tag, signaled by a preceding hash sign (#), used to label content. 

  • The hash sign itself, when used as part of a hashtag. 

verb
  • To label (a message) with a hashtag. 

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