A month’s said to be stunning (5)

I believe the answer is:

amaze

'to be stunning' is the definition.
(to amaze is to stun)

'a month's said' is the wordplay.
'month's said' becomes 'maze' (I can't justify this - if you can you should give a lot more credence to this answer).
'a'+'maze'='AMAZE'

(Other definitions for amaze that I've seen before include "baffle" , "Stagger" , "Greatly surprise, fill with wonder" , "Bowl over" , "Cause wonder" .)

I've seen this clue in The Times.

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