Orally declare sister worried about trophy (9)

I believe the answer is:

nuncupate

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'orally declare' is the definition.
'nuncupate' can be an answer for 'declare' (thesaurus). I am unsure of the 'orally' bit.

'sister worried about trophy' is the wordplay.
'sister' becomes 'nun' (I've seen this before).
'worried' becomes 'ate' (I've seen this before).
'about' means one lot of letters go next to another.
'trophy' becomes 'cup' (cup is a kind of trophy).
'ate' after 'cup' is 'cupate'.
'nun'+'cupate'='NUNCUPATE'

Can you help me to learn more?

(Another definition for nuncupate that I've seen is " Declare".)

I've seen this clue in The Times.

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