ab vs abdominal muscle

ab

noun
  • abdominal muscle. 

  • An abscess caused by injecting an illegal drug, usually heroin. 

  • The early stages of; the beginning process; the start. 

verb
  • To abseil. 

abdominal muscle

noun
  • Any of a group of four muscles that form the abdominal wall. 

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