Dogs, a number wearing coats regularly (7)

I believe the answer is:

canines

'dogs' is the definition.
(canine means a dog)

'a number wearing coats regularly' is the wordplay.
'a number' becomes 'nine' (nine is a number).
'wearing' means one lot of letters goes inside another.
'regularly' means one should take alternating letters (regularly take one letter, leave next etc.).
The alternating letters of 'coats' are 'cas'.
'nine' put inside 'cas' is 'CANINES'.

(Another definition for canines that I've seen is " Dogs -- teeth".)

I've seen this clue in The Times.

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