codex vs speller

codex

noun
  • An early manuscript book. 

  • An official list of medicines and medicinal ingredients. 

  • A book bound in the modern manner, by joining pages, as opposed to a rolled scroll. 

speller

noun
  • A book used to learn how to spell properly. 

  • A person who spells. 

  • A spell checker. 

  • A participant in a spelling bee. 

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