tours de force

/T UH1 R Z D IY0 F AO0 R S/
noun
  1. 1

    A feat demonstrating brilliance or mastery in a field.

    โ€œNow orbiting Earth, Gravity Probe B is a technological tour de force.โ€

  2. 2

    An outstanding display of skill.

Source: https://en.wiktionary.org/wiki/tour%20de%20force, https://en.wiktionary.org/wiki/tours%20de%20force