Area hit badly in old province (7)

I believe the answer is:

rhaetia

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'old province' is the definition.
The definition suggests a singular noun which matches the answer.

'area hit badly' is the wordplay.
'badly' is an anagram indicator.
'area'+'hit'='areahit'
'areahit' anagrammed gives 'RHAETIA'.

'in' is the link.

Can you help me to learn more?

(Another definition for rhaetia that I've seen is " Roman province".)

I've seen this clue in The Telegraph.

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