High roller chap returned in new suit (7)

I believe the answer is:

tsunami

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'high roller' is the definition.
'tsunami' can be an answer for 'roller' (thesaurus). I'm unsure of the 'high' bit.

'chap returned in new suit' is the wordplay.
'chap' becomes 'man' (chap can mean a man).
'returned' shows that the letters should be reversed in order.
'in' is an insertion indicator.
'new' indicates an anagram.
'man' in reverse letter order is 'nam'.
'suit' anagrammed gives 'tsui'.
'nam' going into 'tsui' is 'TSUNAMI'.

Can you help me to learn more?

(Other definitions for tsunami that I've seen before include "Huge destructive sea wave" , "Huge wave caused by earth tremor" , "Strong surge" , "stormy sea" , "Long sea wave" .)

I've seen this clue in The Telegraph.

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