infix vs introduce

infix

verb
  • To instill. 

  • To insert a morpheme inside an existing word. 

noun
  • A morpheme that always appears between other morphemes in a word, such as -i- and -o- in English (i.e. an interfix). 

  • A morpheme inserted inside an existing word, such as -bloody- in English. 

introduce

verb
  • To bring (something) into practice. 

  • To cause (someone) to be acquainted (with someone else). 

  • To add (something) to a system, a mixture, or a container. 

  • To make (something or someone) known by formal announcement or recommendation. 

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