on the fly

Idioms  

1. In a hurry, on the run, as in I picked up some groceries on the fly. The transfer of this expression, which literally means “in midair or in flight,” dates from the mid-1800s.

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Example Sentences

Driving interventions were for things such as parking spots or adjusting the route on the fly.

From Barron's • May 3, 2026

So did Redick, who deserves credit for reacting to the late news of Durant’s absence, as he and his esteemed coaching staff drew up effective adjustments on the fly.

From Los Angeles Times • Apr. 19, 2026

They expertly steer the story around one sharp turn after another, with many a secret exposed and the principals adjusting their outlooks on the fly.

From The Wall Street Journal • Apr. 9, 2026

The Show was created on the fly, based around a drum loop and the theme song to kids' TV show Inspector Gadget.

From BBC • Mar. 25, 2026

During weekends and school holidays, the four of us were inseparable, racing in and out of each other’s yards and making up games on the fly.

From "Courage to Soar" by Simone Biles