coin toss vs heads or tails

coin toss

noun
  • A particular instance where a coin is launched in the air, and whichever side that it lands on finalises a decision. 

  • An uncertain selection between two outcomes of similar likelihood, or between two objects of similar quality. 

heads or tails

noun
  • The practice of flipping a coin in the air, to choose between two alternatives based on which side lands face up. 

How often have the words coin toss and heads or tails occurred in a corpus of books? (source: Google Ngram Viewer )