Muster that's circular and rising (5-2)

I believe the answer is:

round-up

'muster' is the definition.
(thesaurus)

'circular and rising' is the wordplay.
'circular' becomes 'round' (synonyms).
'and' is a charade indicator (letters next to each other).
'rising' becomes 'up' (similar in meaning).
'round'+'up'='ROUND-UP'

'that's' is the link.

(Another definition for round-up that I've seen is " Summary of events".)

I've seen this clue in the Sydney Morning Herald.

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