Crossword Genius

One sister is courting floods (9)

Ross

I believe the answer is:

inundates

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'floods' is the definition.
(I know this)

'one sister is courting' is the wordplay.
'one' becomes 'i' (Roman numeral).
'sister' becomes 'nun' (sister is a term of address for a nun).
'is courting' becomes 'dates' (I can't justify this - if you can you should give a lot more credence to this answer).
'i'+'nun'+'dates'='INUNDATES'

Can you help me to learn more?

(Another definition for inundates that I've seen is " Floods".)

I've seen this clue in The Telegraph.
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