(idiomatic) operational, in operation

(idiomatic) To act in an uncontrolled, unbridled manner. / (idiomatic) To be uncontrollable.

(idiomatic) To undergo a series of tests or challenges.

(transitive with to) To defy or oppose something, especially an expectation, custom, or social standard.

(idiomatic) To behave recklessly. / (idiomatic) To take a calculated risk. / Used other than figuratively or idiomatically: see run, scissors.

plural of run-on sentence

A classroom exercise in which students run to a text, and then pass the message verbally to a partner.

plural of running dictation

plural of run chase

(computing) a set of procedures prepared by an administrator for the day-to-day maintenance and exception handling of an IT system