Rescuing thin bit of wood hotel's thrown out (6)

I believe the answer is:

saving

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'rescuing' is the definition.
(saving is a kind of rescuing)

I cannot understand how the rest of the clue works.

(Other definitions for saving that I've seen before include "Second World War film with Tom Hanks" , "Putting by for a rainy day" , "Cost reduction, except" , "Preventing from dying" , "Rescuing" .)

I've seen this clue in The Daily Mail.

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