A substitute for reticence (7)

I believe the answer is:

reserve

This clue is a double definition.

'a substitute' is the first definition.
('reserve' can be a synonym of 'substitute')

'for reticence' is the second definition.
(synonyms)

(Other definitions for reserve that I've seen before include "put to one side" , "Secure" , "Twelfth man < 's coolness" , "Savings - book" , "Bank" .)

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

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