hanky-panky vs statutory rape

hanky-panky

noun
  • A debaucherous act; a sexual act that is considered inappropriate. 

  • Mischievous behaviour, dishonest or shady activity. 

  • Amorous behaviour, smooching, making out, necking, sexual intercourse or other sexual activity, especially if illicit. 

statutory rape

noun
  • An illegal act of sexual intercourse by an adult with a person under the legal age of consent for sex, or with another adult who is not able to consent because of intellectual disability. 

How often have the words hanky-panky and statutory rape occurred in a corpus of books? (source: Google Ngram Viewer )