think on one's feet

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think on one's feet (third-person singular simple present thinks on one's feet, present participle thinking on one's feet, simple past and past participle thought on one's feet)

1. (idiomatic) When one is in the middle of a process, activity, or conversation, to adjust rapidly, effectively, and intelligently to new developments or changing circumstances.
   • 1901, Henry B. Fuller, chapter 24, in Under the Skylights:

     "There will be wine," said Medora. "Drink it. There may be toasts. Be ready to respond."
     Abner could think on his feet—speech would not fail.

   • c. 1919, Elbert Hubbard, “Richard Cobden”, in Little Journeys, Volume 9: Great Reformers:

     The political canvass had given freedom to his wings; he had learned to think on his feet, to meet interruption, to parry in debate.

   • 2007 September 16, Karen Crouse, “Covering New Ground, Jets’ Clemens Relies on Deep Roots”, in New York Times, retrieved 7 November 2011:

     Clemens had to think on his feet, adjust on the run, make split-second decisions and, if he messed up, contend with the consequences.

• extemporize, improvise

• make it up as one goes along