prep vs trial performance

prep

verb
  • To prepare. 

noun
  • A student or graduate of a prep school, a preppy. 

  • A prep school. 

  • preparatory level; the last two levels or the fourth and fifth years of preschool; the two levels before first grade. 

  • Preparation. 

  • Homework, work set to do outside class time, used widely in public schools and preparatory schools but not state schools. 

trial performance

How often have the words prep and trial performance occurred in a corpus of books? (source: Google Ngram Viewer )