drive-in theater vs drive-in theatre

drive-in theater

drive-in theatre

noun
  • A drive-in cinema; Pedantic form of drive-in. 

  • An outdoor theatre, suitable for concerts, stageplays, and the like; with a parking lot where patrons can drive into, to watch the show from their cars. These have become more common with the need for social distancing in the COVID-19 pandemic. 

How often have the words drive-in theater and drive-in theatre occurred in a corpus of books? (source: Google Ngram Viewer )