dummy runs

/D AH1 M IY0 R AH0 N Z/
noun
  1. 1

    A trial or practice before the real attempt.

    โ€œWe'll try a dummy run with a small group first, to check that it works correctly.โ€

Synonyms

Source: https://en.wiktionary.org/wiki/dummy%20run, https://en.wiktionary.org/wiki/dummy%20runs