Announced roadside limit (4)

I believe the answer is:

curb

'limit' is the definition.
(curbing is a kind of limiting)

'announced roadside' is the wordplay.
'announced' shows a homophone (sound like).
'roadside' becomes 'kerb' (I've seen this before).
'kerb' is a homophone of 'CURB'.

(Other definitions for curb that I've seen before include "Control, limit" , "Check or restrain" , "Restrain, inhibit" , "Rein in" , "[LIMITATION]" .)

I've seen this clue in The Everyman puzzle in The Observer.

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