half-time vs halftime

half-time

noun
  • The interval between the two halves of a sports match. 

  • A tempo in which the rhythm is emphasized so that it seems to have half as many metric divisions (e.g. emphasizing the start of every other bar rather than every bar). 

  • Half or approximately half the number of hours usually worked in a specified period. 

  • The time taken for a physical quantity to halve the difference between its present value and its final value. 

adv
  • In a half time manner. 

adj
  • Pertaining to or characterized by half the usual duration. 

halftime

noun
  • The halftime show, the primary light entertainment of a game, after the second quarter, when players can physically recover, coaches can give players a pep talk, bets can be doubled, etc. 

How often have the words half-time and halftime occurred in a corpus of books? (source: Google Ngram Viewer )