diddle vs solo sex

diddle

noun
  • The penis. 

  • In percussion, two consecutive notes played by the same hand (either RR or LL), similar to the drag, except that by convention diddles are played the same speed as the context in which they are placed. 

verb
  • To cheat; to swindle. 

  • To waste time. 

  • To molest. 

  • To masturbate (especially of women). 

  • To totter, like a child learning to walk; to daddle. 

  • To manipulate a value at the level of individual bits (binary digits). 

intj
  • A meaningless word used when singing a tune or indicating a rhythm. 

solo sex

noun
  • masturbation 

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