This small hound surprisingly re-entered a brier (8,7)

I believe the answer is:

aberdeen terrier

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'this small hound' is the definition.
The definition suggests a singular noun which matches the answer.

'surprisingly re-entered a brier' is the wordplay.
'surprisingly' is an anagram indicator (a surprising ordering of the letters).
're'+'entered'+'a'+'brier'='reenteredabrier'
'reenteredabrier' with letters rearranged gives 'ABERDEEN TERRIER'.

Can you help me to learn more?

(Another definition for aberdeen terrier that I've seen is " Dog".)

I've seen this clue in The Telegraph.

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