headword vs wordage

headword

noun
  • Any word which may be modified by an adjunct. 

  • A word used as the title of a section, particularly in a dictionary, encyclopedia, or thesaurus. 

wordage

noun
  • The choice of words used; phraseology. 

  • The excessive use of words; verbiage. 

  • The number of words used in a text. 

  • Words collectively. 

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