I left in time being nimble (5)

I believe the answer is:

agile

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'being nimble' is the definition.
(agile can mean nimble or athletic)

I can't explain the rest of the clue.

(Other definitions for agile that I've seen before include "Dexterous" , "Quick and easy-moving" , "Nifty" , "Limber" , "Nimble, fleet" .)

I've seen this clue in The Sun.

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