Start in the stable (3)

I believe the answer is:

shy

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'start' is the definition.
(I know that shy is a more specific form of the action start)

I can't explain the rest of the clue.

(Other definitions for shy that I've seen before include "Throw in bashful way" , "Short of" , "Bashful or timid" , "Recoil" , "guarded" .)

I've seen this clue in The Globe and Mail.

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