A rough dress - very rough - for soldiers (5,6)

I believe the answer is:

horse guards

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'rough for soldiers' is the definition.
The definition suggests a singular noun which matches the answer.

'a rough dress very' is the wordplay.
'a rough dress' can be anagrammed to 'HORSE GUARDS'.
However, I am not sure how the anagram is indicated.

Can you help me to learn more?

(Another definition for horse guards that I've seen is " Ceremonial cavalry".)

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