one-on-one vs triple O

one-on-one

noun
  • A contest involving only one player on each side, especially of an activity often involving teams. 

adj
  • bijective or injective 

  • Involving one attacker and one defender. 

  • Involving direct communication or competition between two people. 

triple O

noun
  • A one-on-one. 

name
  • Phonetic rendition of Australia′s emergency services telephone number, 000. 

How often have the words one-on-one and triple O occurred in a corpus of books? (source: Google Ngram Viewer )